In my bathroom, there is a retainer wall that enclosed the shower/bathtub. The caulking around the tub eroded over the years and water seeped through to the exposed retainer drywall. After recaulking the tub, I sanded down the wall, spackled where needed, and repainted, but it doesn't look any better. Since I am new to painting and repairing walls, I am wondering if perhaps I didn't sand or spackle enough, or if I even used the right materials.
So my question is, how do I make this wall look nice and new? Any help would be appreciated!