Battery wont charge after replacing

Have a iPhone4 that has been swimming in the water. After that the battery was charging very slowly and the camera aint working properly. The battery does charge but goes slow and the iPhone gets very warm.

So replaced the battery with an Original Apple. Iphone goes on everything like it shoud be. When plugging it into the charger is shows the charging sign, but in fact it aint charging at all. A strange thing about the battery is that the hole for the screw wasn't on the right place as well. So i coudnt screw it thight. Where to look in this case? a faulty battery, problem with dock connector or another part maybe?

Any suggestions are highly apreciated.

Thank you.

it was the battery itself, besides the battery the camera and the earspeaker have been replaced, everything up and running again.