Is my iPhones battery gone crazy?

Is it normal my iPhone 4S takes only 4 minutes to drop down to the next percent.

It depends on what your doing and what settings you have on and stuff, location settings really drain your battery and so does having your brightness really bright, there's lot of battery apps that can help you. Good luck! One thing I find that really helps that no one really tells you but apple people when you call is when your charging your phone and it hits 100% take it off the charger don't just let it charge all night ect.

It *could* be normal if there are apps running in the background that want updated information so the radios (Wi-Fi, Blue Tooth and/or cell service provider macro network) are being accessed.

To reduce this activity (and increase battery life), turn off the ones you don't need.

From the main menu, touch Settings, scroll down and touch Notification Center. Scroll down and in the "Include" area, turn off the items you don't want to include. You can add them back later if you want.

Press the back button (upper left). If Personal Hotspot is on, turn it off - you can turn it on when needed.

Press the back button (upper left). If you don't use a Blue Tooth device and don't sync using Blue Tooth, then turn Blue Tooth off (if it is on).

There are more but this should help get you start to reduce the power consumption a lot…