Meaning:
“我” means “I,” and “了” is an auxiliary word meaning “in the state of.” A shortened form for “emotional hardcore punk rock,” originally “emo” referred to a subgenre of hardcore punk rock that existed in the late 80’s. Later it referred to a style popular among some teenagers characterized by wristbands, long dyed hair that covers their eyes, skinny fit jeans and skate shoes. These teenagers are sometimes thought of as anxious misfits, and therefore Chinese netizens coined this term to mean “I’m upset” or “I’m depressed.”
Example:
A: 今天丽丽又收到她男朋友一大束花，我emo了。
Jīntiān lìli yòu shōudào tā nánpéngyou yīdàshù huā，wǒ emo le。
Today Li Li got another big bouquet of flowers from her boyfriend. I feel a bit down (because my boyfriend didn’t give me flowers).
B: 每个人表达爱意的方式不一样，不用和别人比。
Měigerén biǎodá àiyì de fāngshì bù yīyàng，búyòng hé biérén bǐ。
People express their love differently; there’s no need for comparison.