Trying to get pregnant

I had a boyfriend for a year and we tried to get pregnant. I had taken a plan b pill once because i wasnt ready for a baby but after that everytime we had sex he would finish inside and i never got pregnant. We are no longer together and havnt been for 6 months. I now have a new boyfriend and yes we are having sex and yes he has finished inside. Not that a want to have a baby but i know what to expect, i also still havnt gotten pregnant and we have been having sex for 2 months. It concerns me, but I want to be able to have babys. Should I go to the doctor? I used to be an extreme athlete about 8 months ago but stopped becuase of college i dont know if that would have something to do with it. I also was always stretching!