I had something similar once when I was taking a narcotic for a pain condition. The sounds went on for a couple of weeks (usually music). I thought there was a radio playing in my attic for awhile, among other things. The problem stopped when I stopped the med.

It's an unsettling thing to happen. I felt a little less disturbed when I realized that the sounds weren't real, but still, if they hadn't stopped when I stopped the meds, I'd have been seeing a psychiatrist about them!

I think that it is possible for doorbells to get an electric short and to ring on their own, but the timing of what you're describing doesn't make that seem like that's what's going on.

I hope you get it figured out. *hugs*