could you tell me what is the product code of your phone? you can see that from the label sticker that is visible after you remove the phone battery. it's the 7 digit code starting with 059xxxx, usually above the IMEI number.
also it might be helpful if you can remember what software version you had in the phone before the update.
if the phone doesn't power up anymore, then the only option to recover it may be to take it to a Nokia Care service point for reflashing.