When i'm happy?or sad

When I'm happy i dance in the rain
When I'm happy i feel no pain.
When I'm happy i laugh and skip
When I'm happy theres a smile on my lip

When I'm happy i DO smile
but "When I'm happy" only last for a while

and then i get sad.....and

When I'm sad i cry in the rain
When I'm sad all i feel is pain
When I'm sad i scream and cry
When I'm happy that smile say "good bye"

When I'm sad i smile?? NO Never
and "When I'm sad" seems to last forever