White screen cant restore

Hi i was hoping someone could help me with my dilemma i just replaced the battery on my iphone 3gs and i plugged it to my computer and at first nothing happened but then when i held the home button i could hear the phone making some noise but the screen was black, and now i tunes detects my phone but it has a white screen i read that to fix the white screen you should hold the lock button and home button to restart but my lock button doesn't work so i cant do that and i saw that you can restore your phone from itunes so i tried to back it up but it says you must first unlock your phone but i cant see my screen so is there anything else i can do ?