My Dilemma

Oh my goodness, what'll I do,
I have a big dilemma,
Maybe sometime its happened to you!
Lets see if you remember,
I squirm and jump and often frown,
And twitch and puff and sometimes wiggle,
I turn my body upside down
And maybe even giggle.
There's an answer to my problem which,
I'm hoping you will catch
You see, I have a great big itch
That I've just got to Scratch!!!