iphone 5 battery is getting too hot and screen popping out from one side

Hi All,

I have been using iphone 5 for some time now, recently it started to get hot while wifi is on and if more than few applications are on. It is not happening consistently hence i ignored it for past month.

Now recently iphone's battery became to hot and screen popped up from one end. Please suggest if i can fix it myself, if not how much would it cost me as phone is not in the guarantee period.

Thanks

varsha