to be unnecessarily over dramatic or extremely overemotional such as Bella in New Moon from the Twilight series
Him : OMG I ordered this with "some" pineapple and they only put a "little" pineapple ! I mean seriously did you not hear me tell them !! How many times do I have to tell them the difference between "some" and "little" !!! Do they not know who ... on and on.
You : Can you zip it! Quit being so belladramatic ... You're kind of a dick anyways.
Similar to melodramatic, defined as "exaggerated and emotional or sentimental; sensational or sensationalized; over-dramatic" ......... but even *more* ridiculous, a la Bella Swan from the Twilight Saga by Stephenie Meyer regarding her entire relationship with nearly everyone in the world.
Oh god, don't be so belladramatic.....you'd think you were just dumped by a vampire.