Lucy says she's always been a bit of worrier, but two years ago she began to get anxious and started having panic attacks.
"I didn't know what was happening and my parents didn't either," says the 15-year-old. "It was scary. The attacks would occur without warning. It got worse and I began to have them in public."
Lucy started missing a lot of school and stopped socialising. She says it was hard for her parents to see her struggling. "We didn't know what to do or where to go."
For six months, she tried to manage her anxiety herself, but eventually the family decided to pay for a talking therapy called cognitive behavioural therapy.
Lucy says it has made a huge difference. While she still has panic attacks, they are much less frequent and she is back attending school and doing the things she enjoys.
Lucy's story is far from unique. NHS figures suggest one in five children and young people aged eight to 25 has a probable mental health disorder.