contractions!?

I woke up in the middle of the night last night having these belly cramps that felt like I needed to have a BM but I couldn't. Gas like crampy pains, I still have them but I don't feel like they are time able because they are coming and going whenever. They are painful but not unbearable. Do these sound like contractions? I'm a FTM at 37 weeks and wasn't sure if what I am expericining is a real contraction?