My iPhone 5S Keeps Freezing?

I got the iPhone 5S a few days after it came out. I have dropped my phone a few times but it wasn't from that high and it was on carpet. Once my phone was in my back pocket and my friend tried taking it out and I turned at the same time, so I fell face-down on the tile floor. I'm not sure if that did anything to it (I had a case on it when it fell). I haven't gone to any bad websites and I haven't downloaded anything that could have caused this. It freezes and then like a minute later it goes to the apple logo, then it goes back to the lock screen. It usually freezes at the camera or photos for some reason. Does anyone know why it does this? Please help me my parents would KILL me if my phone broke and I'm scared because I have to keep this phone for 2 or 3 years.

Let me know if you need more information.

The phone may have damaged internals, that's why it keeps on freezing. Have it fixed by a pro. And please be more careful in handling your phone.