What's going on?? cell phone problems!!!!!!?

Ok so the other day I hooked up my cell (which had no energy to even start it up) into the wall charger. The green little bulb on the charger lights up and everything when I plug it in, but the phone remains dead and doesn't charge. I can tell it's not charging because it should give a little jolt and then show the bar filling up. It's been a week now and still nothing. what should i do????