How bad is this going to mess me up? Should I go back for a re tune?

 

If you mean you were tuned for 92 octane and now you can only get 93 octane, it should not be a problem. My tune is for 91 octane but I moved to a place with 93 octane only and everything's been fine. It probably is a bigger problem if you are tuned for 93 octane but fill up with a lower octane gas.

 

Yes I mean 92/93 octane. I didn't think it would be a huge deal. I've already been driving like this for awhile. Just wasn't sure how much power I would be losing if at all

 

I doubt you would lose any power by using 93 octane. If anything the power should be the same or possibly a tiny bit more. Even if you got re-tuned for 93, power gains would probably by minimal.

TL: DR --> your car will be fine.