37 weeks question

So, today I have been extremely tired, my husband and I ran a few errands this morning and then I came home and napped for 3 hours, ate dinner, and then just lounged around.

Around 6pm my stomach started feeling pretty upset and I ended up having diarrhea (sorry) 4 times. I drank some cold water and laid back down to sleep some more.

I just woke up and my son is moving like crazy just all over the place and sometimes it hurts way low, very badly for 5-10 seconds and then stops. Are these contractions? Wouldn't they last longer if they were? The pain kind of wraps around to my hips so I'm just not sure. I'm a FTM and have no idea what to expect.

TIA everyone!