Pelvis pain!

Hi ladies, well this is pretty straight forward but my boyfriend and i were having sex(cowgirl first) then we decided to do doggy, and when we did my pelvis was aching and hurting as he was thrusting. But when we stopped it didnt hurt anymore. Now i just feel probably bloated? or something of that nature.. before i go to the doctor do you ladies have any ideas what it could be? Ps. Not on birth control, and TTC. I have and irregular period so i never know when i ovulate nor know when i get my period. So any suggestions, thoughts, ideas ladies?