When something has been, or is 'mecked up' then it basically means 'f***ked up'.
It's a handy word for when you're around parents or teachers...or maybe even the queen if you're lucky.
Dennis: OMG..my dog just ate my homework...
Otis: haha...shame Miss Dicksy is gonna kill you.
Dorita: Yh, your ass is grass dood.
Dennis: This is SOO mecked up man. Wtf am i gonna do??
Otis: Don't ask me. I don't have a dog..
The word 'shpappy' means a state of utter happiness, but with a twist. When a person is shpappy their happiness is slightly overcome by spazziness.
Otis: I'm so SHPAPPY
Otis: Cos the reject gooseblob left me alone and finally took the hint that I don't like her. AT ALL.
Otis: I KNOW!!! *dances*
Dorita: Whats your secret??
Otis: *taps nose* thats for me to know and for you to find out.
Dennis: You raped her didn't you?
Otis: *shifty eyes* No...
Dorita: LIAR!!! Gd one tho...