My computer screen won't show:(

Hello,
Toshiba Satellite L755-S5242 15.6-Inch LED Laptop is my computer.
Yesterday I was using my computer when it flashed white and multi colors then it went black. I found that if I laid teh screen all the way back, I could use it. Today I was blocking a site using the host thing. It was working fine. Then it only had 7% of it's battery left so I left it to chargae. When I came back 30 mins later, it won't show. It made a beeping sound and the screen is still black. I recently restarted my computer to faltury settings like four days ago becasue the screen won't work.
What I've tried: Holding the power button for 30-60 secs, taking the battery out, leaving it alone for a while.
I'm at the end of my rope and I really need to get it to work again for my story that I'm trying to get done to send to a publisher. It's only one year old since this August 11! Help!!!