My PV felt a little hotter in my hand than normal so I quickly unscrewed the and removed the batt. Still not sure if it was really that much hotter but I'm paranoid. The thing is, I noticed that the bottom (-) of the battery was sunken in. I'm not sure if it was always that way or if I was push the PV switch too hard (megalodon bottom button) or if it's a sign of battery failure. My question is what should I do? throw it back in or just chuck it? I'm a little worried about using it to be honest.