No, 5 feet is not too high for a bird feeder. Some birds prefer to feed from feeders that are five feet or higher. This is because these birds can see better and fly more easily over tall trees and buildings. Birds that feed at feeders below the ground may not be as successful in locating food from a feeder located 5 feet or higher.
If you want to attract more specific types of birds, you may want to place your feeder at a height that is more suited to their needs. For example, Cardinals like to eat seeds that are above their head, so you might want to place a Cardinal-friendly feeder at 6 or 8 feet above the ground.