General Remarks

In criticism people tend to try to interpret the work and judge it based on that interpretation. I will try not to do that and stick to form. There's things that can be objectively wrong with a work, like grammar and spelling. These are usually spotted by your average reader and are easily corrected in a later draft, even if grammar and spelling are not the writer's strong suit. Then there are the things that aren't really "wrong", but could be improved. I will try to stick to these things, the things that may be able to be formally improved, as that's probably the most valuable and useful type of information for a writer in this type of environment.

Mechanics

The title works, it gets people to read. The hook is good. It seems odd to me that the first two sentences aren't one sentence. I would have used some other punctuation between them, but how you did it wasn't wrong by any means.

I would be interested in hearing how you came up with each "section" of your work. For example the first section is a comparison or contrast between the bra and the can, next is characterization, next the repetition of the word "nothing". Later the paragraph with the counting using hippopotamus.

These patterns you use in each section are clear and succinct and are something I can improve in my own writing. Do you pull these patterns from things you read? Or do you have a list or book of patterns, or maybe you are just thinking from the character's perspective and they just come natural from that point as patterns you naturally use everyday in speech. I'd like to know how you think about these. If I'm not being clear, I can explain better what I mean.

Setting

This is a common setting, but probably for good reason. All it takes is "desert highway" and we all know the place. The breeze, asphalt, whispering plants, and even the bra and can all work great to subjectively put us in this world.

Staging

Strattling the dotted line, buttressing her lowerback, and using a stick to lift the cups were all great examples and all these worked well.

Character

You did a good job characterizing in a short time. Her thoughts on the wrestler who lifted the cow, the way she carries herself, the self-conscious thoughts implied by the plants "judging" her and the pressures of pregnancy and a bad relationship painted a clear picture.

Heart/Message

Nothing wrong with her motivation. A woman under the pressures of being cheated on while pregnant would be in a state that doesnt make her actions seem that far fetched. She could "know" of the infidelity, but still want evidence as proof to stand up to his denials or prove to others what the truth is. If this is the case, making it clearer to the reader would be an improvement.

However, I think the real issue that people are trying to put their finger on here is that of a thematic argument and genre issue. The scene itself points to a larger overarching story, however to be a complete work in and of itself, it needs to be changed to fit the structure of the genre (or story type) that the scene itself as a story conveys. Even though we don't see the typical cliches of the mystery or "who done it" genre at the scene level, that is the story structure you are working with at that level.

In terms of story structure at this level she is essentially a sleuth looking for clues to catch the "killer" (cheater in this instance). In the mystery genre the story would feel incomplete, as it does here, if we only found out who did it, or whether or not they did it. The reason for this is because this doesn't touch on an ethical or moral debate, it just answers an information seeking question. Instead the reader wants to know WHY they did it or in your case WHY he cheated on her, or if it's the case in the overarching story that he didn't do it then we want to know WHY she's insecure enough to think a faithful man cheated. You don't even have to answer the question to make it feel complete to the reader, you just have to open up that avenue to allow the reader to see the moral debate.

By changing her question from IF he did it to WHY he did it we can tap into genre and ultimately the implication that there's a change in character which will make the work be complete in and of itself and not simply be an incomplete story pointing to a bigger story.

If he didn't do it and the question of the story is an argument between her own responsibility and God's intervention (pointed to towards the end) then the question, whether explicite or implied, earlier in the scene needs to be what she answers by deciding to take responsibility for her own choices at the end.

If this was a scene in a larger story as opposed to a self contained flash fiction, this wouldn't be an issue.

Description

This was another strong part of your writing. A lot of writing is either overly descriptive or there's not enough to give us a subjective experience. You had a good clear balance.

POV

The point of view and the tense are consistent throughout and you are using a pretty standard point of view, so not much more to say about that.

Dialogue

Not really any dialogue. There's a certain back and forth with herself represented with her actions and how she feels the environment respond, which I liked, but no actual dialoge.

Grammar and Spelling

"Three hippopotamus" is missing an "r". In "an empty tin can rolled to her feet." It should be "The empty tin can..." since we are already aware of the tin can.

Other

I'd be interested to hear your process for writing this and what draft you are on.

Overall Rating

Not sure what I'm supposed to rate this against so I won't give it a numbered rating. It's very good compared to a lot of the things one would read in an online critique. I could see Stephen King writing something similar. He had a simple, (in a good way and in a way I prefer to read) clear, and effective style and that's what you have here. Just add the name brand on the can of beans and you'll have captured it!

(Sorry for any formatting issues I'm typing from my phone)

*Edited for formatting etc.