My heart rate/pulse was up to 158 bmp

Doctor wants to see me tomorrow morning because labor and delivery said my heart rate/pulse was up to 158 while monitoring me . What does this mean and has anybody else experienced this ? If so what was the cause ? I don't have protein in my urine and the only thing I could think of was how bad my heart races and how I feel as though I'm being suffocated ALLL the time . Due to anxiety is what I'm guessing and I guess the nurses said the same thing because they said "your doctor wants to see you first thing in the morning for your anxiety because your heart rate can't be that high its dangerous ." My heart rate STAYED that high the whole time they were monitoring me .. HELP !