So I thought I'd ask here because you all can be pretty helpful. Sorry if this was brought up already.

I was playing online (PS3) with some random people a while ago and I think my save file got screwed up. Here's what happened: I had already completed both playthrough 1 and 2 and I was in a game with some people who were first going to

* sorry about that, I'm on my phone and it's different*

Anyway, they were going to kill Nine Toes. All of a sudden a level 70 guy comes in and after a while the rest of us are on our final standings and he leaves. Now I have quests that I completed in my incompleted quest list. What's up with that? Am I screwed now?

A level 70? The level cap for this is 61 (Includes with the Knoxx DLC). Just so you know, many people cheats in Borderland's co-op. They alternate the weapons and can give your save files and stats a scratch. It could be it, but have you tried to quit the game etc?