I haven't had any issues like that with my 09, but I'm pretty sure the roof panel is just thin sheet metal. We had a bad hail storm here in the spring of 2012, and I had a lot of damage done to the roof. Instead of the body shop just popping the dents out, they replaced the entire roof panel.
Anyway, the only thing I think you could really do is take it to a body shop and have it checked out. I don't really know what they would do, but it doesn't hurt to ask.