It sounds like you may be feeling very self-conscious about interactions. It took me a long time to learn, but much of the time (I’ve come to realize), “they ain’t studying on me.” Like—other people aren’t scrutinizing me or judging me as much as I think they are.
Plenty of people are so wrapped up up in their own heads that they aren’t paying you any attention, perhaps not realizing how you are reading their responses to you.
Maybe it’s just me getting older, but “when I am an old woman, I shall wear purple.” If others think I’m dressed weird or acting oddly—what of it? I don’t need (and can’t have) everyone’s approval. Sure—there are limits; I don’t want to endanger myself or others, or provoke hostility. I don’t want to be mean to anyone.
If you make overtures of friendship and kindness and are turned away, that says a lot more about others than it does about you.
And for heaven’s sake, start an investment retirement account now. Yeah, I know, “but I’m not making enough, but there’s that shiny thing in the (online) store window, but I’m never going to get old.” Just allot one take-out coffee’s worth of spare change per week. You can up the ante later. Let the miracle of compound interest do its thing.