1mug/glass of milk is 15 gms so that is more then enough to treat a hypo.
All the bread is doing is keeping you high for ever and day

Depending on the bread you are using if you ate the bread as well as drank the milk you are consuming between 45 - 50 carbs which is a meal in it's self. I do find milk good for treating a low but quickest action is glucose tablets.