Do new pads have a breaking in period?
 

Today I had my front pads replaced with OEM creamic pads. About 20 miles after the install of the new pads, I encountered a situation. I was driving on the highway for a while, I exited and had to make an abrupt stop, someones car just shut off ahead of me, and I had to slam on the brakes. My brakes had horrible fade, and I smelled brake fluid, I pulled over and the rotors were super hot.

What caused this to happen?

Do new pads have a coating on them?

Is there a break in period for new pads?

No, pads are no longer supplied 'green' anymore.
There is a seating period but not a curing period.

New pads do not have a coating on the friction side.

You may have a dragging caliper piston.
When you pushed the piston back in there may have been some rust on the piston that does not now allow it to withdraw slightly after application.

If you had brake 'fade' after not using the brakes for some miles this indicates pad overheating.

Another rare problem, is a brake flexible hose can collapse and not allow
fluid to bleed back after application and cause a caliper to drag.

I suggest you have this discussion with whoever did your brakes, nothing is normal.