Casper, I can relate to you situation.
I was not diagnosed until late in life, so I managed to study and work for many years. To complete high school and two degrees I HAD to organise myself into a strict routine and timetable EVERY hour of every day.
After diagnosis, I used dexamphetamine. This enabled me to focus and concentrate on one thing at a time. The change was dramatic – my output as a programmer doubled. I was taking a tab every every 3 hours, and by about 3 1/2 hours I noticed that I was starting to daydream. It really was that noticeable.
NOTE that one change in my behaviour was that due to the focus on boring stuff and less day dreaming, that I was not as creative. So I did not use dex after work, and not on weekends.
A lot of people worry that an amphetamine is addictive. Not with me. I have to set an alarm to remind me to take it.