Medication anxiety help

So I've been on Methylphenidate long release and short release before and both made me so anxious that I asked to be on a different medication. The psychiatrist gave me Amfexa (dexamphetamine) and said it was the last stimulant they could offer me (and the last ADHD medication I can try because I can't take non stimulants due to my reaction to one before). Amfexa has been giving me so much anxiety like the others, but it's made me so much happier, more happy than any of the antidepressants I've taken. I don't want to loose this happiness so does anyone know how I can get rid of this anxiety? I've ordered L-Theanine to try it but does anyone know anything else? Thanks!! :)