Fetal doppler/plus size

Plus size mommas, when did you pick up your baby’s heart beat on the Doppler?

I got mine in the mail today & tried it out & it gave me some off the wall readings, like 250bpm. I obviously knew this wasn’t correct, I couldn’t even hear anything when it would read anything. I figured it was probably because I’m plus size (215lbs) I have an apron belly from my previous pregnancy, along with baby still being so little & possible still in my pelvis. I’m 13 weeks 3 days. I’m gonna try again when I’m closer to 15 weeks just because I see baby again next week & after that I won’t see him until I’m 19 weeks.