MacBook Pro screen went red...help!

My laptop was sleeping and when I opened it, the screen was red. The login window was still there, but the entire screen behind it was fully red. After I logged in, certain areas of my screen were still red-tinted. Closing and logging in worked, but this worries me. Also, sometimes when I open my MacBook Pro after its been sleeping, it takes quite a while for the login window to pop up; the screen is just black. I often have to close and reopen, and sometimes even restart...Could this be related?