> I tried medication but it gives me insomnia
> and a racing heart.
If you are prescribed 20mg Adderall XR or 50mg Vyvanse (or equivalent), then that's an insane first-timer dose.
Pills have risks and side-effects for sure. But so does making zero progress on your ambitions in life.
Maybe you can find something less harsh: http://www.gwern.net/Nootropics
Apparently, some people are more sensitive -- or, whatever term you want to use -- to the medication; for them, a "standard" dose is too much.
If you still have some tablets left and are unsure how your doctor might receive such a notion, you could use a pill cutter to create your own lower dose. If/As you've already been prescribed a higher dose, and given that the medication is not essential to life function and you've already safely been able to discontinue that higher dose, I don't see how trying a lower dose would present any additional risk.
However, I'm not a doctor, you should talk to your doctor, etc. Just... some of them seem to be pretty narrow-minded including about the possible efficacy of lower doses.