Trying to conceive

My bf and I are trying to conceive. He works out of state so when he comes home every month we try try try try. I still haven’t gotten pregnant yet, not sure if it’s because I’m never ovulating when he comes home. I can’t seem understand why. I have gotten checked and doctor told me that my ovaries look good. Sometimes I question could it be him 😞? It’s starting to stress me out when I take a ovulation test and it’s negative. I have two kids 10 and 7, they aren’t his. He doesn’t have any kids, and at first it stressed me out too because I am 30 and he is 28. It made me think something could be wrong with me.I can only leave it in God’s hands at this point. P.S I hope I get pregnant soon.