iPhone 4 won't start

[Hundizz]

Hello, my iphone 4 is acting strange right now.
Firstly, the power button is stuck.
I plugged the iPhone into the wall and laptop and it didn't start up.
I also tried another wire, no luck
Can't do hard reset because power button doesn't work.
The iPhone is jail broken on 5.1.1 and has been for a very long time.

What do I do?
Can someone please help me.

Edit: no water damage either or drop

 

[JediMeister]

Is your phone still in-warranty or within the AppleCare? If neither, you could try a DIY fix, paying one of a number of services locally, assuming they offer iPhone repair, or get an out of warranty swap/battery replacement from Apple.