Is 10 mg of instant release Adderall once a day a normal starting dose?

My doctor started me on 5mg twice a day for the first 2-3 weeks to make sure I didn’t have any issues with side effects. I went to 10mg twice daily for about the next 9-12 months and then upped to 20mg twice/day and have been at that dose for the last 6 or so years. I’d say 10mg/daily to start is right.
Also, it’s probably wise of the doctor to start you on one dose a day, the stimulant effects of Adderall can be very strong. While the effects of Adderall mainly last 4-5 hours, my experience is that it still lingers for several hours after that initial working period. When I first went on it, anytime I took my second dose after 2pm, I’d struggle hard to fall asleep that night, often laying in bed awake until 2 or 3am.
Did your doctor say to check in after a set period of time to discuss how it’s working and possible change in frequency and/or dosage? If not, I’d recommend you do it anyways, especially if you feel like you need to change something. Overall, I think the dosage and frequency is good while you’re starting out, while your body is “learning” the drug.