Adderall is not the only medication. You might you doctor to try a different medicine such as Ritalin or Metadate CD. These are still stimulants, but in another family of stimulants. Good luck.
The medication I first put my son on took about three months to truly do its job. We went and seen a different dr. she put him on a fast acting medication. We defiantly went over the medication and options.
My experience is that some meds take time to have an effect. Talk to his Doctor about what is happening, talk to his teachers and school counselor. He's young. Don't try to change too many things at once, keep a journal, behavior chart if needed. That way you truly know if it's the meds or something else.
My son was started on Ritalin in Kindergarten and we saw an IMMEDIATE positive change (we had known from birth that he'd end up on something and we waited until 12 weeks before K was ending to start the meds. We tried all sorts of other interventions to no avail, he literally did a years worth of "learning" in the last 12 weeks). When he moved from Kindergarten to 1st grade, he was switched to Concerta because it is time-released. It took a little while for him to adjust but he's done well on it.
We find that Spring is when he seems to need an increase in dosage. He still uses Ritalin if he has an evening event that needs him to focus.
I would talk w/ your doctor etc ... has he been evaluated?