My Husband States His Insides Feel Like They Shake, He

My husband states his insides feel like they shake, he gets very hot and starts pouring sweat the does not feel well at all. This has gone on for a while. He has afib but has not taken his meds in a while. He also takes methadone and lortab due to shoulder reconstruction. I think he is diabetic, I am not sure what is going on. Sometimes his hands will begin to tremble for no reason and he becomes weak