I think my phone is broken

Hi guys! Recently I noticed that there seems to be something loose inside my phone. When I "shake" it there's something making a noise. Not only when I shake it, even when I just turn my phone to horizontal I can hear it (the stuff is really loose, like really really loose) and it is a quite loud sound.

The thing is, I took it to the costumer support and they said it was ok but I'm pretty sure that when I bought it there was no loose stuff inside it. I never dropped ir or anything, it just become loose after 7 months of usage.

I just wanna be sure that my phone is ok because if its not normal i will take it to the authorities, considering that samsung refused to pay attention to my case