Toyota Repair: camry 09 LE / 2 AZ-FE 4 cylindar 2.4 liter, digital odometer, speedometer repair

Question
I had to replace serpentine belt and water pump at 37,000 miles. Is this a sign of any other problems The maintenance guide starts inspecting the belt until 60,000 miles or 72 months.
I bought the car new.  I've had it 4 years in November.  My uncle thinks this is a sign that the mileage on the car was rolled back and has a lot more miles than it actually says. What can I do if this is true?  Is this just the start of more repairs to come?

Answer
Water pump failures are somewhat common on this engine, it should have been replaced under warranty which is 5year/60,000 miles powertrain coverage. Setting mileage back on todays computer controlled cars with digital odometer displays is not as easy or common as it was say 20 years ago, unless someone really knows what they are doing, like a speedometer repair shop which has to be licensed by the state it is next to impossible, it is also against the law in all states in the US and a dealer can lose their business license for tampering with the odometer plus heavy fines.