We measure heart rate in beats per minute nor percentages so your post means very little. Remember the 'concerned' are I suspect not doctors merely people who have done a few weeks non specific training to be trainers.....
I would ignore any comments, but why not take your resting heart rate? Relax for at least 10 minutes then feel your pulse at the wrist against a watch. It should be regular. If it is under 80 consider it normal. If not ask your GP to measure it
Good luck