Am I allergic to his stuff?

Samantha
We've been together for almost 4 years and have been having sex for about 3. We always used condoms until like a month ago he came in me for the first time and I noticed it stung, a lot. I have had yeast infections before but this was different. we have sex, he comes, then it hurts. It hurts up to an hour after and it doesn't hurt as bad if I take a shower. I looked it up and it said it could be a yeast infection or I can even be ALERGIC to his semen. I'm almost 20 and this is weird for me. I just got tested for all stds I have none. Should I go to the gyno?