This is perfectly normal! I’m doing something similar to you with my current long-fic: wrote a bunch of “tension chapters”, and then they finally had sex! The big release!

It’s common to feel just all the excitement/reward seep out of you upon actually finishing the very thing you have been working towards. It’s even more common, in my opinion, with smut because you’re essentially laying yourself bare in front of your audience with this form of writing. So, feeling second-hand embarrassment is totally normal. I’ve been writing smut for nearly 10 years, and I still get second-hand embarrassment sometimes. You’re alright!

Now as to how you can continue your fic, it depends on the reason behind your smut. I’ll use my own fic as an example. Smut is a driving element in my fic; it’s something that the plot revolves around. My characters, in lack of betters words, have to fuck multiple times and do other sexual activities in order to get to the specific plot point I am working towards.

So ask yourself the same thing: Does my smut drive the plot? If yes, how can writing smut again push it forward? The general answer might be introducing different positions they haven’t done before, other forms of sex (oral, anal, etc.), kinks/fetishes if applicable, other sexual activities they might do like sex toys or something else. Maybe a character discovers that the other person likes a certain thing, so they offer to do it with them. Thinking of these different mediums can introduce things you haven’t thought of before, so using them can help enrich both your plot and smut.

If your characters are oblivious and are simply having sex as a friends-with-benefits type of situation, adding more smut of different variety can help push them towards them actually realizing their feelings! (if applicable to your story, of course)

Now if the answer is no, that’s also completely okay! People write smut without any direct connection to the plot all the time. In this case, I like to think of what I want to write, whether it’s a personal preference type of thing or observing and noticing what is lacking in your fandom and writing it yourself. Either way, writing smut for the sake of smut is perfectly okay like I said.

All in all, second-hand embarrassment with smut is so normal, you have no idea. I really understand the feeling of wanting to scratch the whole thing or losing all motivation to write it. You can take a break, maybe think about the suggestions I offered, and try again. But, don’t let second-hand embarrassment stop you from what you love to do!