My iPhone battery is going down super fast?

Okay so I have the iPhone 4 and my battery has always been average but recently it's been going down so fast I charge it every night an over night I've always done that my mom said maybe I " over charged it" but that sounds kinda stupid haha can anyone tell me why this is happening and what I can do thanks.

Be sure you have the latest iOS update (6.0), check to see if blue tooth is enabled as that could influence it. Other services like push mail or apps using location services can drain the battery faster as well. Overcharging doesn't happen with modern batteries. And switching between cellular data and Wi-Fi frequently can drain too.

The only real thing that destroys batteries is heat, keep it away from the sun and make sure you have the stock charger. If your iphone is getting hot while charging then find another charger, you are running to many amps into a battery which causes it to overheat and reduces its life significantly. "overcharging" shouldn't occur if your charger was made in the past several years.

to check the amps, look at the back of your charger and read the label OUTPUT. It shouldnt be more than 1A.

Update your iphone your iphone is probably on ios 4.0. This version had lots of problems like draining the battery within 2 hours and glitches.