I have these white tiny pimple things on the tip of my tongue? they sting if hit by water or food or anything really and it's uncomfortable what is it

Could be many things: The tip of the tongue is densely innervated. A burn or other types of trauma can inflame the papilla at the end of your tongue- those 'tiny pimple things'- and cause them to be hypersensitive to water and food. See your dentist to diagnose it more thoroughly especially if it does not heal by itself in a couple days.

See a dentist: Most likely it's the surface of the tongue that does not have any papillae on them. See your dentist to have him look at them to give you accurate diagnosis.