36 weeks, sitting down for about 30 minutes now...

Kaylee
My heart rate is at 119 bpm and I'm having a hard time breathing...I feel like I just walked up 20 flights of stairs. I don't know how else to describe it...is this normal? I'm in the same clinic as my OB at another appointment but I feel like I've been bothering them a lot lately...I don't want to go there if I don't need to.