Save game corrupted?

Ok, this is kind of a long story so here goes. I was screwing around in the Weapon Crafting Arena and built a Compact Plasma Cutter with an Earthgove Frame, I also upgraded rate of fire as far as I could. When I began firing the weapon Isaac became all shaky and started flying around the screen. When I attempted to save and exit the game crashed. Upon returning to the game, I found my 100% completion file had been reduced to 0%, it also no longer displays my game mode (New Game + or anything for that matter). I also happened to have my resource bots out at the time, and when they returned to the bench I received upwards of 900,000,000 ration seals, and negative 2 trillion somatic gel among other things. I can no longer play online on this file (it always says I'm in an incorrect game mode), and "save and exit" crashes every time I try. My next closest save file is about 70 hours behind that one. I hade all the MK V parts, and had completed just about everything. I've tried fooling around with the cloud/local save system and there's no obvious way to fix the problem. Is there any way to repair my file, or return it to an earlier state? I would really appreciate a response, thanks for your time.