Chronic Migraines and Work

I started working again a few weeks ago and the callout limit is 3 days every 30. I have been out of work for a week due to an awful migraine. I have not confirmed my disability with them, however I never said I didn't have a disability (checked "prefer not to say" on the application b/c I wasn't sure if this was listed under disabilities at the time). At least one of the managers is aware I have chronic migraines. I think I can fill it out Monday since I don't work until Tuesday, which is when I would know if I've been fired. Am I protected under ADA or should I start looking for a new job?