Try to hang in. Stools and stomach noises are going to be going all over the place now with your nerves. Just try and disregard it for now. It's kind of an anxiety free-for-all with your digestive system at this point. It was right before mine at least.
The good thing is: IF they should find a polyp, they get rid of it right then and there. Polyps take quite a long while to become cancer, and that's IF they are the type that become cancer. Some don't.
So consider it a good thing that it there were something there, it won't be for very long.
Keep doing the deep breaths and try relaxing more at night with tea and a good TV show. Everything will be fine!