Tore front camera cable opening phone - Now phone doesn't turn on

I opened my iPhone to try make sure the home button cable connectors were securely in place for a different problem. When I opened it, the screen assembly came off suddenly and I completely tore the cable that connects to the front camera. After closing it up, it wouldn't turn on. I tried opening and checking all the connections a second and third time and got the same result.

The phone has some power though. When I hold down the power button and both volume buttons it will give a brief buzz. Once the battery is reconnected, the upper right hand corner of the phone (opposite side of the rear facing camera) gets VERY HOT after a few minutes . I tried plugging the phone into a computer, but it did not register on itunes. I also tried calling it, but it didn't ring. So it's more than the screen not working.

Can the behavior described above be attributed to just a torn front camera cable? Or is it likely that I damaged one of the other three cables (digitizer, screen or home button cables) that are attached to the screen assembly?

Thanks in advance.

Dave