Q: My 2001 Chevrolet Blazer won't start after installing radio

I recently installed a radio in my Chevy blazer. I disconnected the negative terminal on my battery before I started. Once I wired The radio up I cranked it to make sure everything worked well, I listened to a song for maybe 15 seconds then turned it off and started plugging up the rear hatch button and the 4wd buttons and my headlight switches. Could I have blown a fuse by doing so without having my battery disconnected ? It won't even make a click or clank when turning it over. As I go to insert my key into the ignition it goes bananas and the rear hatch unlocks as if I was pressing it 10 times in a row. My dash lights go very dim then off when I try to turn it over. The radio won't turn on or anything now and I even charged it for 2 hours with 40 amps. I tried jumping it off as well but to no success. When I open the door and turn my lights on it seems fine but as soon as I insert the key, the car dies.

My car has 170000 miles.
My car has an automatic transmission.