Another dumb question: How do I know if a certain problem is covered by the factory warranty? Just call the dealer and ask or is there somewhere I can check on my own?

The problem is that the left part of my hood doesn't lay as flush as the right side, and because of that I think it's causing it to vibrate at higher speeds (75ish).

 

That could be an indicator that the front end of your car was most likely involved in an accident, and the dealer will most likely not honor the warranty for that.