Scared. Advice?

First, I'm 14w3d with twins. So today my boyfriend had drill, he's usually there until five. His mother, sister, aunt, and a few other invited me to go to the flea market and then to a birthday party for his aunt. Well, when we got there me, his aunt, and sister were looking around and out of nowhere I passed out and was told I hitt my head twice. One off the shelf and then again on the floor. I had no clue what was happening. I thought at first I was going to have an anxiety attack because sometimes I get those. Then I got light headed and went down like a sac of potatoes. His sister called an ambulance and his aunt carried me to a chair. They told me everything came back fine with bloodwork when I went to the ER. I wasn't there very long and they sent me home and told me to call my doctor in the morning to get an ultrasound. I feel tired but other than that I feel kind of fine. The problem is my stomach hurts, it feels swollen and sore. They told me I didn't land on my stomach but it hurts.. I have no way to get ahold of my doctor until morning and the ER here is shit and just sent me home. What should I do? Should I be worried? They used a Doppler and told me the heart beats were okay but , my stomach is killing me.