often monitors such as you are wearing are notorious for randomly going off. If you were having a serious problem you would know it. I am going to suggest you call the clinic that ordered the monitor and ask them this same question.
I am on chemo and they have new infusion pumps that are so sensitive they beep constantly. Last time I had chemo it would beep every couple of minutes for the last half hour. I was about to turn it off and head for home - it was very anxiety provoking as the nurse had to manually reset and fuss with it.
It is the little things that push us over the anxiety hill.
Smile and take a deep breath - you are OK.