In the later levels of this game it's very easy to get lost, especially when every place you go to can look similar to the others. What ends up making each place stand out is where the bodies of the guards you've killed in there are, more so when they keep doors open. There are only so many places you can search however so it's simply a matter of time before you find your bearings again and begin progressing. There's no time limits in the game save if you're attempting to defeat the par time. I'll certainly get lost more in this game before this game is done..