Are you on drugs for the mono? Are you actually a confirmed case of mono? Or are you just saying you have mono because you are tired?
There is so much wrong with this question.
First of all, a high heart rate
isn't going to kill you, the fact that you are nervous will increase your heart rate. I'm terribly afraid of doctors, every time I go, my blood pressure rises. I am white coat syndrome
to the max. I check my blood pressure at home and it's never high, only when I go to the doctor, or when someone else is watching.
How old are you? I have a rapid heart beat because of the drugs I am on (prescription, not street) I asked and my doctor told me it's not going to hurt me. He would take me off them if the pounding in the chest bothered me
If you are out of shape, that can contribute to a rapid heart beat.
If you are worried why didn't you ask your doctor about it