Stomach feels hard and heavy

Heather

FTM here. I'll be 29 weeks Monday. Since last night, my stomach has felt extra hard and heavy. It's not contractions because it's a constant feeling. Not painful, just uncomfortable. It literally feels like a 25lb (my weight gain so far) sandbag is strapped to me. UGH! This feeling has come and gone before, mostly at night after eating dinner, but I'm still uncomfortable this morning. It doesn't help that I've been eating horribly lately, only getting 4-5 hours of sleep a night, and I'm super constipated and gassy. Is this normal growing pains? I had an elective ultrasound yesterday morning and baby girl is measuring in at about 2lbs 12oz. Don't think it's dehydration because I'm drinking at least 100oz of water a day.