I think mood disorders can affect sense of time, for one, though it sounds like you have good reasons to wonder about having ADHD.

But don't forget, it's not necessarily "ADHD or what," it could be "ADHD and what." Some ADHD treatments are relevant to other conditions, and vice versa, but there are some overlaps that require a different approach from straight ADHD, so it's best to keep an open mind.