Feeling numb during intimacy

I’ve talked about this with my therapist today but she couldn’t figure out what it was. While I’m with someone like either making out or sex I have these like moments where I feel so numb,empty, and like drained for 2 minutes but then it goes back to normal. It’s not a feeling of insecurity or disinterest in the person I’m with, as I LOVE physical touch. Has anyone else experienced that?