I was driving and hit a pothole really hard, as soon as I hit it it sounded like glass shattered all over my car?

There's no shattered glass anywhere that I can see and when I drive now I can hear something rattling around like a whole bunch of Little Rock's what could it be? I have Ford Focus

Possibly damaged your catalytic converter, it's a part of your muffler system that helps reduce harmful emissions. I recommend having a muffler shop like midas check it

If the noise seems to be behind you, I agree with Marty, it's probably the muffler or catalytic converter. Most exhaust systems rust from the inside out and a large shock can cause the rusty baffles inside to disintegrate.

If I could look all over the car I could tell you.

Did you hit your head on the roof?