The difference between the two spells was night and day - while Kingsley’s had made his face hot, Madam Pomfrey’s made him feel like his face was on  fire. A pained yelp escaped him, but no sooner was he flinching back, then the heat was replaced by a blistering cold that made Harry feel like his face had been pressed against a wall of ice. Just as quickly, the sensations receded once more, and Harry could finally breath through his nose, and see through his left eye.