Answer:
Maybe you have some sort of allergy. This isn't always the case, maybe you got water up your nose and its coming back out, or maybe you have fluids that need to leave your body. Or just maybe you're sick. In which case wear a mask when going outside.
Explanation:
Psychology Major here! :) Hope this helps:
1) Up to date, there is still no definite answer when it comes the capacity of information a brain can withhold - it is truly unlimited.
2) The size of a brain varies between species and its capacity to retain information varies as well.
3) Humans have the most complex psychological process to understand, however, there are many other species who have incredible cognitive intelligence. (Such as dolphins, for example.)
4) When damage is done to a certain side of the brain and there is a need to remove the damaged area, there is a possibility that the undamaged parts of the brain can take over the same functions as the removed area. (Therefore, for example, the remaining part of your brain can still nearly function to a maximum capacity depending of the severity of damage... as well as area).
5) The brain named itself "brain".
(The brain controls you, but you control the brain.)
I got hit with a baseball right in the back of the skull, I saw two of everything for a week and I still had to carry a block of ice home every afternoon.
Wiles became interested in the solution to the problem known as Fermat's Last Theorem