You know I noticed that you have mentioned how sensitive he is several times now. Of course, if someone is anxious or always getting yelled at for being in trouble (typical for a child with ADHD), they do get sensitive...or depressed, etc.
However, there is another disorder that often is mistaken for ADHD or can exist along with ADHD and that is Sensory Processing Disorder (sometimes called sensory integration disorder) or SPD. I think it might be worth your time to check out this link. It might be that "something else" that you are wondering about. The link is - http://www.sensory-processing-disorder.com/
and we have our own forum on the subject if you have any questions. That is here -
http://www.medhelp.org/forums/Sensory-Integration-Disorder-SID/show/1396
Of course, one reason he does more yelling at home is because his meds are probably worn off, and he gets more impulsive, etc.
Working with kids with ADHD is really much more difficult and different then working with a child without ADHD. Unfortunately, pediatricians don't usually have the time to tell parents how to help their children. Here is a good link with lots of basic ideas on helping an ADHD child. I can also usually supply specific links for specific behavioral problems. Anyway, let me know if this is helpful. The link is - http://www.onhealth.com/tips_for_parenting_a_child_with_adhd/article.htm
Finally, do let me know what you think about the stuff on Sensory.