bpdruins, if I take my stimulant medication too late in the day, yes, I do have insomnia. I think just because you couldn't sleep for 2 days doesn't mean you don't have ADHD. The dose could have been too high or it is not the right med for you. It is best not to experiment with meds on your own but get your diagnosis and prescriptions from a clinician. If they think you have ADHD, they can titrate the med over time to reach the right dose for you. That's great you have an appointment with a doctor. Good luck!