I'm at the doctor and I'm 36 weeks and they was doing the baby's heart rate then the nurse went to get another nurse so…

I'm at the doctor and I'm 36 weeks and they was doing the baby's heart rate then the nurse went to get another nurse so she could hear the heart beat then they asked if I have had caffeine today and I said no .. they are gonna do an ultrasound to check my bp.... is that bad I'm a wreck now that something could be wrong