Welcome to the site.

Wanted to suggest if you are still feeling the knot and seeing the redness.
That you call the person who did the procedure. This is first a question as to whether this is part of that. I'm guessing it was a neurologist.

Secondly, with having seizures, as a parent of a 20 year old who has had them for over 14 years. Its possible to have hit your head or did something
in a seizure. You don't even realize you had.

Donna