Please Help Emergency

[Cutiepatooties]

I installed another gmail account on my phone. As soon as it was done setting up, the phone has been completely wacky. It keeps rebooting and is continuously rebooting so much it's not giving me a chance to delete the account i just put in or do anything for that matter. I took the battery out, turned the phone off. It keeps saying Media scan running, Media Scan complete, then shuts off but the lights on the bottom are still on but the screen turns black.

What's going on with this phone? Does anyone know what I can do?

[M91-30]

take the battery out, hold down the power button for 15 seconds, let it sit for 15 minutes, then try turning it on. if this fails, bring it to your local retailer.

[Cutiepatooties]

why after i installed another acct could this have happened? i already took the battery out, turned the phone on and off,

[M91-30]

did you do exactly what I said? just pulling tha battery then putting it back in is NOT a hard reset. I don't know why it's doing this, but you don't seem to be listening to me, so peace.