Is something wrong?

First time mom.. 33 weeks and 4 days. All day I have been extremely tired, having diarrhea, and feeling just completely awful. About an hour or so ago, my back started hurting really bad, now it feels like my stomach is starting to cramp up every now and then. I've been drinking water, tried taking a warm bath, and have taken medicine for the pain but it isn't helping. Is this normal?