Can someone explain why i don't do damage?

I'm a Jax main, tried every runepage and item combo for effectiveness, was a jungler for a while but got bored so went to top, and that's where S*** get's weird.

With Jax, level 1, i do about 60 ish damage per auto with press the attack, when someone else plays Jax in top, same runes and items. They do around 80-90 damage per auto at level 1! Note, they take E first just like me. With yasuo and darius it's even crazier. While I'm doing around 50 damage with single auto, they do around 70-80. And that's with the same runes/masteries. I don't understand. How is it that they are doing more damage than I am with same items, same runes/masteries. At first I thought it's my imagination, but after about 200 games, 20 of which I watched replay for, I don't see a single thing different. The only common thing that there is in all those games is that enemy starts on the red side, the top/right side. So team side impacts damage output? what does the blue team get then? If red team gets flat out damage buff then what is the blu teams buff?