ok.i also exactly have the same psp like yours.i also did the same thing and i upgrade to 5.50 gen d3.my psp got fully bricked.Listen to what i say.Go to the shop where u bought the psp and u must change ur psp's motherboard because now ur psp has been totally spoiled and if u want it to work again,u need to change the motherboard which is slightly expensive.Reply me after u have changed the motherboard.P.S PSP 2006 sucks