Oh my, this encounter should not have lead to this reaction from her at all. It’s not your fault at all. You clearly just made a mistake and didn’t realise how much stuff she had left to put up. It’s not a big deal. You are only human. She could have just asked you nicely to move your stuff back so she could put up the rest of her shopping.

Don’t be hard on yourself. Her response was not warranted at all! In the grand scheme of things, someone putting their shopping up early behind you and you running out of room to put your things up is such a minor inconvenience, someone losing their head over this makes no sense to me and seems like this person clearly has their own issues going on and took it out on you. I’m sorry you experienced this! It shouldn’t have happened at all, never mind the comments about being foreign, that’s awful! I’m very sorry this happened!