I don't if I'm too small or the guys I've been with are too huge

So here's the thing. I'm always the guy with the smaller penis. I'm 5.5" erect and compared to all the guys I've hooked up with (more than 30) I've never come across someone as small or equally small as me.This makes me think that I'm either below average or I've been really lucky. Of course, the whole thing makes me insecure.