I agree with @lisalucier that it must have been surprising and frightening to have a grand mal seizure after so many years. Have you been taking meds for seizures during the past 16 years?
I can also understand your concern if you cannot see your neurologist until the end of December. Did you explain to them about the grand mal seizure?
I would urge you to find some support for your seizures. Here is a website for the Epilepsy Foundation, https://www.epilepsy.com/connect. if you click on the link, you might find some helpful information.
Would you post again and let me know how you are doing?