Not sure what you mean by "cookies", but if you were doing what I've heard of as "donuts" (tight circles with the steering locked to the stops), then you most likely sheared a pump shaft. Trailvoys HATE to be driven in circles in the sand at high RPM because the pump isn't designed for that kind of abuse.
Many reports of failures over the years here - wish you'd discovered trailvoy before hurting the vehicle.
You should probably change the pump anyway. The self-healing might just be a temporary line-up of the cracked shaft, which could come loose when you least expect it in a highway debris avoidance incident.