It may have something to do with GABA / glutamate balance. GABA is calming, glutamate is stimulating. You can try calming supplements like l-theanine and magnesium. You may need to take them through out the day and before bedtime, like four times a day. Any form of magnesium is good (magnesium glycinate, magnesium taurate, etc.) except magnesium oxide, which does not absorb well.
Also check your diet for things like aspartame and eliminate them (any artificial sweetners, MSG, etc. )