I think if my Dom did that to me, he wouldn't be my Dom anymore.

Unless your sub is into urine play, that would be completely uncalled for. If she's not into urine play, I'd call that abuse, especially if it's a limit for her. If you want to punish her, find a better way to tell her you're not pleased with her blowjobs if that really is the case.

If you do it just to do it and then lie to her, well, you're what we call a "wannabe Dom" around here. It's your job to take care of her and let her know that she can trust you completely, lying to her is a good way to kill that bond you two have.