Kay Ska self-harmed for two years and one of the reasons was because she didn't know how to deal with her feelings "in a healthy way".
"I think it was just a lot of confusion, hormones and a lot of image issues," she told Newsbeat.
The 23-year-old is speaking out after figures from the NHS show the number of girls admitted to hospital for self-harm has almost doubled in two decades.
The NSPCC says the statistics are "sadly unsurprising".
Kay, from Lancashire, has struggled with mental health issues, such as depression, eating disorders, self-harm and PTSD.
She runs a blog where people share their mental health stories.
"I really didn't like myself at the time when I self-harmed, I was very negative and in a very low place and I was angry at myself and the world around me."
NHS figures show girls aged 18 and under were admitted to hospital 13,463 times in 2017 - up from 7,327 times in 1997.
Common reasons behind self-harming include depression, bullying, pressure at school, emotional abuse, grieving or having relationship problems with family or friends, according to the NSPCC.
The same rise hasn't been reflected in boys however - with figures showing admissions of around 2,000 have stayed the same in the last 20 years.
Kay thinks the rise in admissions for girls has a lot to do with the pressure that the media puts on women.
"I think media has had such a huge and bad impact for women because you don't see them doing that to guys," she says.
"In almost every single magazine they are body shaming women."
She says social media has a significant part to play too.
"People are following perfect social media accounts and they think that the airbrushed photos are true and it's all real when it isn't."
The NSPCC said the figures were "heartbreaking" but "sadly unsurprising".
Chris Cloke, head of safeguarding in communities, also believes social media is a contributing factor as to why more girls are being admitted than boys.
"They're bombarded 24 hours a day with these perfect images and we know if you're a young person, if you're a girl, you're very conscious of what you look like, what you feel and what other people are doing and this of course also puts pressures on you.
"If you've got problems in one area, they can all add up and they may lead children to be very vulnerable and that may lead them to self-harm."
He said he would encourage anyone who is experiencing mental health issues or thinking about self-harming to tell someone.
A Department of Health spokesman said an extra £300m will be invested to provide extra help in schools, including training staff to support children faster.
For help and advice on self-harm visit the BBC advice pages.