Why dont my speakers or headphone jack work?

My speakers for talking on the phone and listening ti music do not work at all and i cant use headphones either you start the music and no sound comes out.my camera on my phone is also not working every time i open the camera app it gives me a notification that the camera has failed. this phone is 2 years old i got it of September 9th 2014 i just want to know if my phone is fixable or if i just need to get a new one.PLEASE HELP ME!!!!!!