The number of games you personally do has been discussed on the board before. Some refs are younger and in better shape than others, love doing games, and some are just a glutton for punishment.
I'm not as young as I used to be (of course, none of us are) and I did nine Rec games a few weekends ago (Sat and Sun) and was a bit tired and stiff on Monday. I've seen stories on this Forum of some refs who've done 7/8/9 games a day!
How well you do can depend on your conditioning, the age of the players, level of play, size of the gym, half court set games vs run and gun games, etc.
Bottom Line - If you sign up for 22 games in a week, you get what you ask for - and hopefully, you're still giving your best (same level) effort in the last game as in the first. If you can do it.....more power to you!