What Causes Upper Stomach Pain And Constipation During Pregnancy?

I am 28 weeks pregnant. I Woke up in the morning feeling bloated but hungry. By the evening, I was having severe upper stomach pains. They are not contractions as they do no lt come and go and get progressively worse, this is a constant pain that sometimes radiates to my back. It gets worse when I lay down. I tried passing stool and that briefly gave me relief for about 15 minutes. It was small, hard, and smelled like a perm solution. This has been going on for about 4-5 hours with no relief.