Did you hear the sentence correctly? Perhaps you heard , "Why [ are] you mad though?"

I think the question you heard is "Why you mad dog?" Not "Mad dough." Why you mad dog? Means why are you mad friend? Dog is something that you can call any friend, but it is usually just males that use the term. Mad dough is in fact another term. It means a very large amount of money. "Wow, that car must have cost you some mad dough."

I can only presume it means "a lot of money". Either that or it's very peculiarly shaped bread. :)))))))))))

well basically it means that you have a bad attitude as an opposite of a cool person , when someone adress you " why are you such a mad dough ? "

Thanks a lot Allen!!! I usually use urban dictionary as a habit. I just didn't look for in this time because I felt it is as just a friendly sound they do like you said to just emphasize or be more confirmative on what they say. Thanks a lot for your explanations!!!