Seizure triggers, response timing

I have not officially been diagnosed with Epilepsy.  I have had a few nocturnal seizures, and all of the test show normal results, etc so we are still trying to identify the causes of my seizures.
If something in my diet were triggering the seizures, like maybe aspartame or alchohol, how long does it normally take for a seizure to develop?  A day, a week?  Shorter, longer?
My seizures happen once every 6-8 weeks, its usually only one and its at night while asleep.  I am doing a sleep study soon as well.  Any tips would be extremely helpful.
Thank You

[Narble]

Seizures can be triggered by excess alcohol consumption, but this happens within a matter of minutes to hours. It is more likely that you have no one specific seizure trigger, which is the case for most seizure disorders.

The sleep study should be very revealing. Also useful is a 72-hour ambulatory EEG, or a 24-hour video EEG (performed in a hospital setting). I hope you can find out what is going on and begin effective treatment soon.