@crawfordjake475 Well, I think you can set your mind at ease that anything you were feeling immediately after inhaling the leaf was NOT the result of any parasite.
Why?
First, the cilia in your nose are quite effective at pushing unwanted matter back out.
Next because it's unlikely there were live amoeba hanging out in chlorinated water.
Finally because it would take quite some time for any amoeba to travel to your brain and multiply to cause symptoms- think weeks or months.

If the celery leaf is still in your nose, you could use a saline rinse and gentle blowing to get it out.
How are you feeling today?