Yeah, I realized after I posted that I didn't really put enough examples in there.
I'm generally pretty shy, but when I'm comfortable with someone I get kinda clingy and tend to not shut up, even if the other person can't hear me or walks away.
I get obsessed with foods, movies, music, etc. For example, I'll watch the same movie over and over every day for like a month or so, until I move on to another one. I also stay on the computer too much, playing solitaire over and over until my contacts get so dry I can't stand it anymore.
I'm a housekeeper at a hotel and have the same exact routine in every room I clean. I do everything the same way, in the same order, and if I have to do something new or change something, it completely throws me off until I find a way to work it into my schedule.
I don't know about stims or meltdowns though. I do pop my fingers all the time, clench my jaw when I'm nervous, bite my lips when I'm trying to focus, bounce my legs, play with my hair, talk/sing to myself, and when I'm really tired, I rock myself to sleep or rub my feet together until I fall asleep. As far as meltdowns, I sometimes get angry easily. If my mom or someone jokes around with me relentlessly when I'm in a bad mood, I'll lash out. If I can't do something on a small scale with my hands, like threading a needle or something, I'll get so incredibly angry I want to throw things and I'll start shaking and have to walk away for a bit.
Maybe these are better examples? I'm sure there are plenty of other examples that are slipping my mind right now.