I would think that you may have dislodged a connector or even the mic itself.The parts are available and not TO expensive. But it looks to me like the teardown is reather extensive. I include the link for you to check it out so that you can see if that is what you would like to do :) good luck

for the part http://www.cellphone-repair-shop.com/sam...

for the teardown http://www.wikihow.com/Replace-the-Scree...

even so this is for the screen, it will get you to all the parts and pieces.