Hey Dyna, I'm in 30 weeks now and also experienced diarrhea, throwing up and pain in the lower right ab. Went for check up last few days and was given some pain relief medicine accompany with prescription from gyne that I might have suffered from food poisoning. The advice was to take as plenty of rest as possible. Now feel much better already, but constipation is terrible.
I think the best for you is to have check up at any gyn near by your location and have prompt attention to the situation.
Wish you get well soon!