I have noticed that I tend to have random periods where I feel sort of hyperactive. Well, most of them (some are) aren't exactly random. My sister just asked if we were playing Mario Kart tomorrow, and I said 'yeah' in a weird voice, and now I'm in this state.
For example, for about 15 minutes I will make threads like this, shake my legs excessively, make random weird facial expressions, and talk like this to my friends online:
'LOL!

:D:D:D:D:D:D:D'
'XD <.< >.> :L'
And I have no idea why. XDXD
I do other stuff too. I don't feel happy or anything during this period, just sort of a dull 'high' or something. There are other times that are different, but similar in a way. It's kinda hard to describe when I'm not experiencing them in the current moment.
Is this being happy? What is 'happy' for you?
It sounds like what I call being manic or wired or wound up when I'm feeling things that way.