I dropped my iphone 3gs and music won't play through headphones?

So i dropped my iphone 3gs and it seems like the top half of it (internally) doesn't work. What i mean is that, the lock button doesn't work, the volume and vibration buttons don't work, and whenever i plug in my head phones to listen to music now it just plays through the speakers. I tried multiple headphones. Anyone have a fix or am i doomed?

Those elements of the phone are connected by a flexible ribbon inside the phone that runs along the outside edge and connects the various boards and connections for those functions. An experienced repair person could take the phone apart and determine if the ribbon has merely been disconnected from the main board or if the ribbon is damaged, or if the connection points are damaged. The cost of these repairs would have to be weighed against the fact that the 3Gs is essentially obsolete, possibly making finding that replacement ribbon difficult.