Screen won't turn on, but phone is functional.

I was in the middle of texting someone when my phone screen started glitching out. Then the entire background had this blue hue and it just turned off after that. It would glitch on and off for a couple minutes, but now it's not doing anything. If i hold down the power button it vibrates indicating the shut down option popped up, but the screen remains black. It still vibrated to indicate messages and emails too. The light for the charger started blinking, so i plugged it in; but when I came back, it had overheated and now my phone is completely dead.