Period sex

I get so horny on my period, it's unreal. I can't resist my boyfriend. 
He's never had period sex before. I have and I have loved it. It feels so much better. 
So last weekend, I got my period and we planned too have sex as I was spending the night at his place. He said he didn't want too get bloody everywhere. So I lay a towel down on the bed. We got in to it & his penis flopped. Instead of allowing me too get him hard again, he just rushed off for a shower. 
What do I do? 
Is he disgusted perhaps? 
I was loving it.