Hi, I know I’m replying late and this thread is a few months old but I experience sleep issues as well.
I have gone to a sleep neurologist and he taught me a lot of tricks that helped. One being to shorten your time in bed. You say you’re getting into bed early, which may be the problem. My neurologist tolls me that if you start out with shorter times (like 11pm to 5am) your body will begin to become more efficient with sleep, as it learns that that is the only amount of time it’ll have to sleep. Then slowly increase the length of time.
Also, don’t bring any electronics into bed or watch tv. If you can’t fall asleep within 20 minutes of getting into bed, go somewhere else and do something relaxing until you’re tired (not electronics or tv- reading, writing, painting etc.)
Personally, I’ve felt like my mind is quite active at night and had read somewhere that a low dose of stimulant medication may actually help some people with ADHD sleep better. You should try to talk to your doctor or find another one and maybe look into different medication options.
I hope some of this helps and wish you luck!