Stomach pain

Hey guys, I’m currently 21 weeks, but 2 different times this past month I had this horrible stomach tightening. it felt sharp and tense all over consistently for about 5 hours while at work. It made me nauseous and I threw up from it.

It gets better with rest. I always drink about 3 liters of water a day.

The first time this happened I had a uti and took antibiotics. The second time they didn’t find a cause.

Could it possibly be Braxton Hicks? Doctors are tossing it up to round ligament pain but I don’t think that would last so long, or make me nauseous?