I just got my car service at the dealership for my 100,000 tune up they performed a coolant fluid exchange then nine days later my coolant pump breaks is that normal?
100,000 miles is a "normal" amount of miles for a water pump to break in the sense that it is not unheard of for that to happen. Its difficult to peg a number to how long to expect that a water pump should last because there tends to be a lot of variability. My friend's water pump went out in that ballpark, I'm not sure the exact number of miles but his car was less than 10 years old at the time.
Water pump failure could also include a blown water pump gasket. My BMW sprung a leak from the water pump at around 140K. My dad has had the water pump gasket blow twice on his Mazda B2200 and he only has 170K on it. (its a 28 year old car, just low miles).