Cramping after using fetal doppler

So I'm 11 weeks and I used my fetal doppler for the first time this afternoon and it took me around 20 minutes to find the heartbeat.

When my fiance got home he wanted to hear it too so I tried again for about 10-15 minutes and got frustrated that I couldn't find it again and stopped.

Now 2 hours later i'm have very mild period like cramps.

I'm actually freaking out a good bit.

Is cramping afterwards normal?