The way to deal with heat is already well known by the Indians...

Yoghurt! Either in Lassi (a yoghurt based drink, often drunk before the meal, to line the stomach and protect from the hot spices) or in Raita, a yoghurt, cucumber and mint condiment served with the meal. If you are faced with a curry that is a bit over the top, some raita on the side (or plain yoghurt if you don't want to change the flavor much) and it calms it down quickly.

In fact, any time you make something that the heat gets out of hand (you might have got an extra potent batch of chillies), stir in some yoghurt or sour cream, and much of the heat goes away.

And follow the meal with a light dessert made with milk or cream, maybe a nice cardamom flavored rice pudding or even simple ice cream, and tomorrow won't be quite as agonizing!