So latley (last year and a half) my social status has changed from "perfect" to...?

Do you have to do anything? If you say that 'emo' describes you accurately, then just be emo. You're a teenager, so there's nothing wrong with that (just remember to grow out of it later... trust me). If it annoys you then you can either find a way to 'make fun' of your friends in the same way (if it is a joke as you say), or just tell them straight out that you don't like being made fun of. Don't be aggressive about it. Also try not to give them any fuel to work with - by saying something like "just writing some lyrics" you are walking into a situation where they can easily make fun of you. Just leave it as "nothing much" and ask them what they're doing instead. You can still LOOK emo without being overdramatic about the connotations, if you want.