Kicked in the stomach...

So I run a daycare and had a new boy today who is 6....he was throwing stuff at my head, throwing a tantrum, cussing, hit my daughter in the head and kicked me in the stomach! Needless to stay he will not be coming back! Anyways my question is I'm 20 weeks pregnant and I'm having lots of pain and some cramping now since the boy kicked me in the stomach. I'm not sure if I should go to the doctor or not???....