I just got a Dovpo Punisher 80 a couple days ago. It's my first mod and everything seems to have been working fine but a little while ago I retrieved it from my jacket pocket and it was very warm to the touch and the battery that was almost full 6 hours earlier was dead. I don't know the brand of the battery but it's a 18650 3,000mAh 3.7V. Is it the mod or a bad battery?