Broken screen, computer won't recognize phone

I recently dropped my 5, and it didn't crack but the lcd screen had 3 white lines on the right side of the screen and that side stopped functioning, i could still answer and make calls with siri, but couldn't unlock, later the entire screen went black, and now when i plug it into the computer, it makes the charging noise or vibrates every 5 seconds, but my computer won't recognize it, and itunes tells me i need to unlock it before i can back it up, is my phone a total lost cause? or is there some way i can back it up or fix it? thank you!