We have been having issues with one of our showers draining slowly. Tried different things (snaking, drano, etc) and no go. I suspect that the drain may be busted or corroded, as I could not even get the snake past the p trap.

Tthe house is on a slab. The shower is fiberglass. I will get a plumber over to take a look but in the meatime, gather some opinions ahead of time.

Am I in trouble? Is there anyway to replace drain without destroying the shower?