“Heart rate ”

I have started using Metamucil to help reduce my cholesterol. Since using it I feel lighter and have lost a few pounds. My resting heart rate during the day since starting this can sometimes be 55-60. I also take metoprolol for high blood pressure and a heart arrhythmia. I have had a lower heart rate before occasionally usually an hour or two after taking my first dose of metoprolol in a day but I don’t notice it often as I am usually working and moving around. Right now I am off work that’s why I noticed it more. Is this problem that my heart rate is lower ? I feel fine while it’s lower. Maybe a bit more tired but I am also sitting quiet and relaxing and I take other meds that make me feel tired after initially taking them in the morning. I have recently had a check up with my doc and an ekg which was normal and my blood work done was normal except for my cholesterol.