Water pumps

My car is a pontiac sunfire 2000 with 196311 miles. I recently got a oil change, air filter, tune up, fuel injection cleaning, and replaced the serpentine belt. Two days later, there was a growling noise coming from the engine when the car was in idle. I noticed coolant coming from under the car after it had been parked for 15 minutes. The coolant resevior was full. Could this be my water pump? They also checked my hoses for leaks.