Dreams.

And also, that stupid feeling right after you wake up, like life isn't terrible and everything is good. I wonder what they pump into your brain to create that effect?

Lasting a minute? I don't think so.

It's some kind of unfamiliar state. If you've had enough sleep, but not too much, you might feel better in the morning due to the optimal functioning of your body, when everything in it works as it should, but then it would last longer than a minute. And I don't see any other factors that could play a role.

Many men experience happiness for only 20 seconds.

I can't agree, alcohol intoxication can last much longer.