I DONT KNOW HOW TO FEEL!

So this guy who I randomly hook up with like one or twice a month, tonight I went over (I didn't tell him I was on my period) with intentions of giving him a blowjob (he had other intentions). While giving him his blowjob, he tells me he wants to feel me on him and I tell him "no." and he said "period?" I said "yes". He went and grabbed a towel and sat it underneath him so I could fuck him while on my period..... First time I ever had sex while on my period. I don't know how I feel now. It was great and all. I just don't want him to be disgusted.... he took a shower afterwards and backed my car up afterwards and turned it around so I could leave (I hate backing out of his driveway) so I always ask him to do it for me.