Tramadol and bradycardia?

Has anyone else on a beta blocker experienced bradycardia after starting tramadol? Or a similar pain killer? I've read a few things saying it's rare but possible, and I'm trying to pinpoint why I'm suddenly having such a low heart rate when I normally run high.

Context: Cardio put me on metoprolol several months ago for POTS, no side effects or issues. Mildly lowered my base heart rate. Different surgeon gave me tramadol for recovery this week (unrelated condition), never had issues with it in the past. On metoprolol my bpm usually runs in the 80s at rest and 120s moving, but suddenly I'm in the 40s-50s even when I'm moving. Overall feeling run down and have a bounding pulse, lots of nerve vibrations. I'm uncomfortable, but not seeing any emergency signs I've read to watch out for with bradycardia. Is this normal or anything I should be concerned with? Thank you!