I'm freaking out at my girlfriend because I thought she cheated on me
Are you sure that that is what happened.
No she's cheating on me just because I have a small penis
You are insecure because of your size, but to take it out on your girlfriend is just wrong on so many accounts. Take your pride and get some self esteem, she is not going to put up with that freaking out forever. Then you will be sorry and lonely if you don't stop acting out.
You don't know what it feels like 2 be me I was born this way and it's fine.
You should try not to freak out so much then. You should be able to trust that your girlfriend is not cheating on you.