Hypothyroidism - After Thyroid Removal - I just had my right thyroid removed how do your heart rate?

Well I had this procedure done almost 13 years ago and soon after I did not notice any changes but months to years later I have been with a heart rate of 125 to 170 and had been prescribed beta-blockers to lower the rate, some made me sick with nausea and others had me extremely jittery, I am not taking any as of todays date but still have heart palpatations from time to time, and nothing would ever set them off, just a normal routine.