30 weeks pregnant with our first baby and this past week I've just felt terrible. I've had some lower back pain that comes and goes, when I have it though it feels like my lower back muscles are tightening and it lasts about 5 minutes and stops. I've been so tired, and I am not hungry at all but I am still eating even though I definitely don't want it. My stomach has been hurting a little bit on and off but I'm sure that just might be constipation. Is this normal? I'm more concerned about the back pain than anything.