Resting heart rate of 54 to 60 sometimes

I usually monitor my heart rate through my apple watch, when checking the data of my heart rate for last month I noticed there was 6 days in total when I resting heart rate range was between 54 to 60. I was taking ciplar LA 20 since July and before that I have taken Petril beta for 2 months. Just wanted to know is the resting rate of 55 for sometime is normal and also to add when I workout or go for for running then my heart rate goes from the range of 150 to 180 beats and comes back to normal range after sometime when I stop working out. Is this normal or should I get some test done. Note- I have done my stress echo test done last December and the test were normal. Please suggest is this normal or should I get some test done.