First off those were two of the lamest "You're so ugly" jokes I've ever heard.

A better joke would be:

Yolk: You're so ugly that when you were born, the doctor looked at your mom and said, ''This is going to cost extra if I have to spank his bottom."

Or

FMB, You're so ugly, your mom had to be drunk to breastfeed you!

As for some schooling:

YTMND = You're The Man Now Dog

Oh Snap = generally considered an expression of disbelief usually after getting told.

Getting told = being insulted.

Example of good use of the phrase OH SNAP:



Urban flow chart for the proper use of "OH SNAP":



Class dismissed.

Sunil, go stand in the corner.

JHAP
~~~~~~~~~~
"My mind is a raging torrent, flooded with rivulets of thought cascading into a waterfall of creative alternatives."
...Hedley Lamarr (that's Hedley not Hedy)