DSM 5 does not include mood swings as a criteria for ADHD but many experts feel it should. Most patients with ADHD complain of mood swings. This can lead to confusion about possible bipolar disorder but in ADHD, the swings tend to happen on a many times a day basis which is uncommon in bipolar, and more often are event driven, even if that event is trivial. The hallmark of Bipolar is the ups, feeling GREAT, better than others, invincible, over confident, even more silly than normal, not needing much sleep.
The mood swings in ADHD tend to be from the patients normal to down or angry and are not usually associated with INTENSE rage. Upswings are almost always because something good happened.