Meaning: oops upside your head

Hello
I have some questions concerning a song from Snap "Oops up"
here is the lyrics:.

Ey I wanna say I say oh ah hey hey hey ooh oh oh
everybody say opala somebody say opala
here's what I want to do
--

Ah just put your hands in the air
and wave 'em like you just don't care
well if you really like me and rock real free
somebody say yea somebody say yea
--

Oh say oops up side your head
say oops up side your head
everybody say opala
hey yea say oops up side your head
say oops up side your head
everybody say opala
--

This is a song about those bad days
start out happy and end up sad days
talking about that Murphy's law
if you think it go wrong yes it will
went to the store to cut some protein
Firday night and I had the munchies
filled the gut till it couldn't take it
one more bag of chips would break it
went to the checkout stood in line
behind me was a girl who was too fine
got in the end while they rang the total
reached for my wallet uh-oh a polo
not my day I felt like a dummy
went to the story and forgot the money
--

Oh say oops up side your head
say oops up side your head
everybody say opala
hey yea say oops up side your head
say oops up side your head
somebody say opala
Everybody say oops up side your head
say oops up side your head
say opala
everybody say oops up side your head
say oops up side your head
everybody say opala
--

Me and Amy under the covers
seeing uns hot potential lovers
demon in the sack is her reputation
if school is sex she's the graduation
touching holding heavy breathing
I knew I'd get her she's mad about teasing
left on the light so I could see reaction
Amy's a freak guaranteed satisfaction
she's as soft as a bubble bath
I'm as hard as a Chinese mat
ready for the ultimate affection
took out the pocket got my protection
rolled it up in one hard stroke
it was my last thing yes it broke
--

Everybody say oops up side your head
say oops up side your head
somebody say opala
say oops up side your head
say oops up side your head
somebody say opala
--

A little Miss Muffet
sat on the tuffet
eating her hurts away
along came a spider
and sat down beside her
said what's in the bowl bitch
what's in the bowl bitch
Hey yea yea hey yea yea
what's in the bowl bitch
hey yea yea hey yea yea
what's in the bowl bitch
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My first question is what is the meaning of "Oops up side your head"
and the second question is what is this all about? In general, what are they going to say by this song? What is the concept behind these verses?

what is the meaning of following verses:
Ah just put your hands in the air
and wave 'em like you just don't care
well if you really like me and rock real free

-----------

and these:
A little Miss Muffet
sat on the tuffet
eating her hurts away
along came a spider
and sat down beside her
said what's in the bowl bitch