CSMicros

The very first thing to do is go back to a place where it worked. Remove the button and just clip the screen back in, if that doesnt work try another screen to rule out the new one you have isnt faulty. If not then put the old screen back on and go through dfu reset again. The other issue you have is if you didnt use any antistatic pads, straps etc then there is a good chance youve fried a chip on the board.