Hi. I think a lot and unnecessary stuf. 4 days ago i was watering the lawn, an ant a little bit big in size with a very little large headed from the small ones, crawling on my leg. i took it in my fingers and was throwing away but it slept, but i got the thinking in my mind that did that go into my nose. i didn't feel itchy but kept on snorting out heavily. was searching the internet for the nasal cavity and its passage, where does it lead to. to the brain or to the stomach etc. now today i saw a spider of a kind that is smaller than a normal coin, which jumps a lot and fast, i went towards it and thrashed it with the cloth i had in my hand. i was some 3 5 inches away. it cleared away, but i got the feeling again, did that go in my nose. again i dont feel itchy at all, but my mind is thinking this ****. as a doctor you tell me two things, where does the nasal cavity leads to. is our brain protected through the nasal cavity? can any insect survive inside the brain? does the brain fluid contain enough validity to kill any living object, if it enters the brain? and finally if there is something goes into your nose, how it feels like to have in your nose, what a person might feel? itchy sour? hard to breathe etc etc. please help me out. thanks. will x-ray shos something.? Thanks