This made me laugh, thank you for that.
why did that make you laugh?
Bro, you're not a sociopath.
If you were a sociopath you wouldn't be on this forum seeking advice. Were you actually a sociopath, you would see nothing at all wrong with your misdeeds even were you to recognize that you manipulate people. Sociopaths usually only begin to feel upset when they realize that they are incapable of feeling anything at all. You clearly have emotions and regret the times you feel that you have wronged others.
Relax man, most young men at some time or another obsess over a girl and go to great lengths in order to win her back. This is typical if she finds you clingy. I've been dumped for being clingy, and in all likelihood if you were what you fear you are then you would seem the opposite of clingy to this girl.
Just take a deep breath and reassure yourself that you're ok. You're obsessing, and that can be a symptom of an anxiety disorder, nothing more.