You need to reduce the evening dose to 1/2 or 3/4
You are not taking into consideration the half life of adderall which is 12 hours. Even though your XR dose has worn off you will still have amphetamine floating around in your system so the evening dose is amplifying the earlier dose because of the half life. This will also carry over into the next day and the next day and etc….
This is a very common problem often remedied by a simple reduction in dosage
By the way, which brand or generic is your XR and the evening IR????????
It is also possible the IR is a better/stronger generic than the XR/ER form you take in the morning.
Half life of adderall messes up a lot of people until they figure out the correct dosages, and the inconsistent generic strengths don’t help.