Hi and welcome. It seems there are lots of things you have learned about yourself and how to be in relationship, and I do hope you don't beat yourself up too much for mistakes made. You are young, so give yourself a break. I was once told by a very wise teacher that our 20s are meant to be about fucking up and discovering who we are. We all make mistakes and, unfortunately, we humans tend to remember the lessons learned through mistakes more than lessons learned any other way.
If I were you, I would slow down and not jump in too fast into new situations. Give yourself time to get to know someone before making big decisions or getting involved physically and emotionally with people. Do what you can to always honor yourself and build your self-esteem, while making sure to be as empathetic and compassionate as possible, and you'll be way ahead of the game.
The world opens up... when you do.
Oh, oh, can't you see? Love is the drug for me. ~Bryan Ferry
"Love is that condition in which another person's happiness is essential to your own." ~Robert Heinlein