Try not to worry too much about it, Kawika. There are a LOT of us out there in a similar situation.
I'm allllmost 6' 3" and <data concealed> pounds, so my size ensures that my junk looks small by comparison. I could be mammoth and still look underequipped. That had me convinced for a long time that I was really tiny, and while finally running across the stats on what is considered average made me feel much better, I still carried those poor-body-image scars.
What helped me more than anything, though, was just what it sounds as if you have found: a relationship with a woman who loved and appreciated me and with whom I was sexually compatible. Coming to a point of trust and respect in a sexual relationship was immensely healing for me, and I hope you find that to be the case as well.
Plus, finding the LPSG and the great people here, discovering that there are many men who struggle with the same uniquely male issues I have, has helped me feel more at ease than ever. I hope that your time here is as beneficial for you. You are definitely among friends.
Hang in there, buddy! :smile: