Use 'histrionic' to describe actions that are excessively emotional, often to the point of being fake or insincere. She put on a histrionic sob upon hearing the mild criticism.
Pro Tip 2/3
Attention Seeking
Describes behavior intended to draw attention or appear more important or special. The student's histrionic antics in class disrupted everyone.
Pro Tip 3/3
Not Always Negative
'Histrionic' may be used humorously or affectionately to describe someone who is theatrically expressive. Grandpa's histrionic storytelling makes family gatherings so much fun.