Dumb question

So im a FTM and ive been trying to time my contractions when i have any that is, and i find it difficult to figure out when they end b.c the pain starts strong and then dulls to nothing but a tiny (tmi) but like a small upset stomach diarrhea type feeling. So i rlly dont get if they just go and die down or go and stop completely. I feel so dumb but i rlly don't know lolz