Yeast infection constantly after dating new guy?

So I’ve been seeing this new guy, and I’ve only had one yeast infection before. But me and my boyfriend have only been dating two months and we are pretty sexually active and I’ve had at least 4 different yeast infections. It’s not as itchy as it is painful, maybe it isn’t a yeast infection?

I wiped today after I peed post sex and there was brown little dots that looked like lint on the toilet paper? What the fu*k is going on! Diflucan helped for a day but then I got another infection, probably should see a doctor.

He hasn’t been checked for std’s and I’m worried he may have given me something.