I Had A Urine Culture Test And A Swab Test

I had a urine culture test and a swab test done and found out I have heavy growth of staph after 5 days of having unprotected and oral sex with my boyfriend. 4days after sex, I noticed my urine was cloudy, later a bad smell now a peppery sensation while I pee. I told him and he panics that he's never had unprotected sex but with me and he's furious suggesting it's from me cos he's urinalysis came out clears days before we had the sex. I know it's not from me cos I run a routine check up every 3-6 months. Now the relationship is threatened. I'm not particular about who's to blame but for him to get a test done n treatment if required cos I've started mine with an antibiotic cipro.
I'm anxious and not happy too. What do I do? Also I've not had sex for 8 months until I met him. Hmmm...