I've Been On Metformin For Years And Over All I

I've been on metformin for years and over all I was doing well. I started taking Vyvanse 6 months ago. Therr dosage was gradually increased and I've been on 60mg for the past 3 months and in the last two months I've experienced migraines for the first time in my life, don't have a normal sleeping pattern, have random bouts of exhaustion, struggle completing tasks due to hyper focus on others, and I've gained 20lbs.

Is this likely a reaction to the 60mg dosage of vyvanse? Of vyvanse itself? Our something completely unrelated?