Joint pain with Metoprolol 50 mg

A few weeks ago, I was switched from Diltiazem 125mg to Metoprolol 50mg. Shortly thereafter I had a successful cardioversion, and it appears that Metoprolol is doing what it is supposed to with my BP and pulse rate at good levels. They are close to what my BP and pulse rate was before the onset of AFIB. The problem is that I now have some rather severe joint and muscle pain in my right arm from the wrist to the bicep. According to information that is available joint and muscle pain is a side effect of Metoprolol. I see my cardio in a about a week, but curious if anyone else has suffered, or is suffering from joint pain while taking Metoprolol.