Okay, additional info. I was vaping at what read 3.74V with a 2.0 carto for a couple of minutes, steady, but not really chain vaping, and it got so hot between the button and the 510 connection that I couldn't hold it in my hand. BTW, I'm using brand new freshly charged 14500 protected Trustfire flames.
I waited a few seconds and took the back of the case off. The glue was so hot that it stuck to my finger when I touched it(I know I shouldn't have touched it). The case has melted a tiny bit right between the button and the 510 connection. This is my first VV mod, but I am pretty sure this is not normal.