iphone 4 wont turn on

over the past few weeks ive been having problems with my iphone 4. Recently its been saying "no service" so i cant recieve calls or texts and its been getting really hot and a temperature thing pops up on the screen saying cool down and then last night the phone completley turned off and wouldnt turn back on! it now has the apple logo on the screen constant and ive tried everything for example holding the home and sleep button and it doesnt turn back on and ive tried holding the + volume key button as well. The phone is fully charged as now it is plugged in charging, Is there anything else i can do which will make it come back on? and could it be my battery? someone help pleaseeeee