My Husband Is On Metoprolol And Has Been Experiencing Sweating,

My husband is on metoprolol and has been experiencing sweating, chills and runs of ad in with pain. In the past this was caused form pain and/or low magnesium and potassium. I have given him potassium and magnesium purchased OCT. We can't get in to see his cardiologist until tomorrow as the office is closed. He has no pain tolerance . He doesn't want to go to the hospital because he doesn't believe they can do anything to stop it. Can I give him more of the magnesium(250mg) and potassium (99mg). They gave him magnesium and potassium I've when he was in the hospital a month ago having a colostomy reversed.