He ghosted me

So I’m extremely embarrassed to even explain this on here but I just need advice. I’ve been seeing this guy for 5 months now and we have been intimate over a number of times. I thought we were extremely close I considered him something like my best friend. But one night that we were having sex when we were finished when I got up and looked on his couch I had leaked out a little bit of brown discharge. It’s nothing I haven’t seen before because to my understanding it’s old blood. But the day I had sex with him my period marked a week ago. And I was in my ovulation time frame. But when he saw the brown discharge he did a disgusted face and I asked him why he was looking like that he just told me he had a lot to do in that moment.. but that was a lie because he hasn’t texted me ever since and we usually talk everyday. Why would he ghost me over that?