SVT Ablation - Question

I’m three months post-op and my EP didn’t put me on any meds other than Tylenol, doc recently prescribed me Indomethacin (25mg x3 daily) - today I was checking my HR and my watch was putting me mainly in the 60s but also lingering in the high 50s, I thought post-op HR would be higher, anyone else experience this before? I’m not feeling any pains but it is spooky seeing them 50s pop out.