Been falling down the rabbit hole 4 hours

Sure, I'm on Vyvanse. Have been fairly consistently (said every ADHDer ever) for more than a couple years. As for today, it's been out of my system since this evening...and yet here I am, at 2:50am, up and wide awake as though it's 1:00 in the afternoon. I mean, what the hell??? I have two kids and a job that will be fully expecting my best at 6:30 and 8am respectively. I don't know if my insomnia is related but I had a massive (like to the point of an upset stomach) headache earlier...well yesterday evening. Thoughts?