Prima Donna = Italian phrase that literally translates as "first woman," it is now associated with its usage as the common term given to the female lead in an opera. Since soprano starlets are infamous for being both talented and high-maintenance, it's commonly used as a pejorative for people with talent who are high-maintenance in other fields.
Pre-madonna = an illogical neologism created by people who phonetically guess at the spelling of "prima donna" without understanding either its origins or meaning; it makes no sense at any level, so don't use it if you want your words to carry more weight.
Are your FB practices like something out of dead poets society?