Johnny Rotten complex
A behavioral disorder, in which the patient behaves like a complete and utter belligerent arsehole because they are trying, vainly and way too hard, to be as punk as humanly possible. Common among snotty teenagers, but most outgrow it.
Kelsey used to be cool, but she developed a Johnny Rotten complex, and now she's this little bitch who tries way too hard to be oi oi punk rawk.