After E1M2 of heretic i start off M1M3 With all the keys and i have not typed in a single cheat code. also after finishing the lvl and going in to M4 i still have all keys at the start of that lvl how do i turn it off so i can play the game the right way?

I think this could be considered a bug, it seems a problem with MAPINFO.

Yes, it's because of the MAPINFO changes. It already has been fixed some time ago.