The parents of a teenage girl who was stabbed at school have described their desperation as the situation unfolded, with her mother overseas and her father unable to get a phone signal. The 15-year-old girl is recovering after being stabbed in the back by another pupil at Thorpe St Andrew School near Norwich on 11 March. Pupils were told to switch off their phones and hide under desks as the school was placed under lockdown in response to the incident, and armed officers arrived at the scene. "It's been a mix of emotions – a rollercoaster. Terrifying, grateful, very up and down," her mother told the BBC. "I was abroad when I got the call. I had to get home as soon as possible. "Words can't express how you feel. You wish you just had superpowers to get home. "At first, I wasn't really aware of whether my daughter was stable enough. I wasn't getting the answers I should have.…