That must have been super frustrating for him, as well as the coach, because I doubt he would have been left in if he wouldn't have had the perfect game going. They may have ended up over-working him for nothing, which would suck.
Definitely hard work to pitch that many pitches, and at the end of it for nothing which is disappointing to any pitcher honestly. He'll have to sit out for a day or so to get that arm back.