Dell says my HD is broken- true/false?

Hello, I dropped my laptop yesterday and the computer seemed to be working fine until about 20 minutes later, when I went back to check on it. The screen was black and the start-up screen (where it says "Dell" and there's a little loading bar at the bottom) kept showing up as if the system was working and then it would freeze at a black screen and the fan would make a whirring noise before showing the starting up screen again- about every 2 minutes. Of course I call Dell's tech support, who tells me that the HD is broken. Now, I'm not sure if the dude was taking advantage of the fact that I'm no comp. expert at ALL, but I had to order a new HD for 200 bucks. I started researching all of this info today when I had internet access in front of me, is there any way to check to see if my HD will ever work again? There are NO cracks on my computer, no apparent physical damage. Last night when I talked to the tech support guy, he made me run a few diagnostic tests on my laptop which had error messages saying "Could not read/write disk" or something. In the most simplistic terms possible, can anyone give me advice on how to check if my files can be saved/extracted from the HD? Thanks.