Heart palpitations during sex?!

So the last week or so I’ve noticed something new. When I’m having sex with my husband I’ll have heart palpitations. Anyone else experience this? I don’t get them when I’m doing other strenuous activities, so I figured it had something to do with blood flow/increased heart rate perhaps. They started at the build up to my orgasm and stopped soon after I had an orgasm. I was constantly checking my pulse during that time and it was a little elevated but not abnormally high for during sex. It went right back down after.

I used to have heart palpitations a lot when I was younger/with previous pregnancies years ago but I haven’t had them in years and being a hypochondriac, it’s terrifying for me and now I’m afraid to have sex. My midwife appointment isn’t until next week so I figured I’d see if anyone else has been having the same thing.

Also, I was laying flat on my back so perhaps it had something to do with positioning? I’m 16 weeks. I’m so paranoid I can’t stop checking my pulse now. 🙁