Piper Cherokee pilot reported they temporarily lost control of the aircraft while landing and veered off the runway into the grass. The pilot was able to taxi back onto a taxiway to parking.

Narrative

Stabilized approach using full flaps; touched down at 60 kts. according to ForeFlight Track log. On rollout; the plane veered to the left and entered the grass between the runway and adjacent taxiway. I regained directional control while in the grass and steered between two taxi lights to enter the taxiway without further incident. To the best of my knowledge; there was no damage to the aircraft or airport property. Brakes seemed to operate normally and equally after the incident. Tires appeared to be properly inflated. The return trip to my home airport went without further incident.This was my third landing of the evening on this runway. Because it happened so fast; I didn't have time to evaluate what went wrong in the moment. I suspect that since I was anticipating a full stop that my feet were covering the toe brakes. During the rollout as I tried to maintain centerline; I suspect that I inadvertently activated the left brake without equal pressure on the right brake; starting the veer while still traveling at 50 knots.