I had cried so much I looked like a prawn. Someone else was in the ladies' loos as well and I longed for them to leave. I heard the click of lipstick and started sobbing again. What was happening to me? It was the same thing that too many teachers struggle with alone: stress-related anxiety and depression.
Research from the NUT recently revealed that half of all ill health retirements from teaching are caused by stress or psychiatric illness. And one in three teachers will have mental health problems because of the stress of the job - well above the national average.
Why are so many people in this caring profession in such pain? One reason is the difficulty of knowing whether you are clinically depressed or just unhappy. Depression doesn't give you purple spots. The symptoms are common to many: sleep loss, changes in appetite, low energy and feelings of hopelessness. So when is it an illness, and when is it just a pain in the arse that will pass in a week or two?
The answer is when it doesn't pass in a week or two. Insomnia eventually sent me to my doctor. I thought she would give me sleeping pills, but she signed me off work for two weeks and recommended a clinical psychologist. "Loss of enthusiasm, withdrawal from others - these are symptoms of depression," she said.
When you are depressed, there is no pleasure in the present and no belief in the future. The colours of life drain away - its tastes and its laughter - leaving an agonising void. Any stimulus can give you pain - a snatch of music, a flower bobbing in the wind. Imagine what a shouting class can do.
You can feel worthless and ashamed, not wanting anyone to look at you. And it makes you almost too tired to lift a spoon.
I felt wobbly when I was told I was mentally ill. But if I had known then what help was available, I wouldn't have been so afraid. I went private, to move fast. The therapist was great: "I see a lot of teachers," she smiled. It was a huge relief to speak to this friendly, unshockable woman who had no preconceptions about me. I went to her for cognitive behavioural therapy - CBT. This helps your poor, sad brain to think clearly. Then you can make choices - big or small - to change your life and feel better.
I calmed down. I learned to sit on benches rather than just run past them. Talking things through helps you to stop torturing yourself over things that are not your fault. You look at the evidence, rather than believing your own misery. "They'll fail and I'm crap!" may mean that you are ignoring signs of progress. It can sound like obvious stuff - when your mind is healthy. When it's ill, thinking clearly is like trying to climb stairs with broken legs. It hurts, and you need help.
Depressive thinking is destructive and rigid. "All-or-nothing" thinking is one example, where only one outcome will do and all others are unacceptable. The teaching profession fosters just this kind of destructive thinking - the kind that CBT helps patients to fight. Ofsted needs some CBT. It thinks that "satisfactory" really means "unsatisfactory". Peel yourself off the ceiling, Ofsted. You'll feel better if you do - and so will the rest of us.
Therapy helps you to crawl out of the ditch rather than just find secret ways to live in it. Teachers are good at that. I developed a fear of driving, and kept seeing mental images of mangled bodies. Now I realise this was a symptom called "intrusive images". I just drove to school an hour earlier, to give me some weeping time in the car park. Horrible images were my brain's cry for help. It makes sense: if it had shown me cupcakes I wouldn't have done anything.
Symptoms like this can disappear with therapy alone. If they do not, you may need medication as well to help you get better. I was guided through this by a calm psychiatrist who drew helpful diagrams of my brain, and by one concise and reassuring book: Depressive Illness: The Curse of the Strong by Dr Tim Cantopher. The Royal College of Psychiatrists' website also helped, with its excellent online leaflet called Depression.
After a month on Citalopram, I was less tired and stopped seeing images of people pulling their own eyes out. The shame gradually lifted and the ability to feel pleasure returned. I still had more crawling to do, but medication gave me the strength to do it.
So why is there a stigma about anti-depressants, when they help so many people? One person told me: "Popping pills won't help. You've got to do it yourself." You wouldn't tell a diabetic that, would you? The media loves stories about people who beat depression by repairing pogo sticks or eating fish. That's great - but some people need the pills as well as the fish. So what? Depression is not an exam, and medication is not cheating.
There is such suffering in the world that depression can seem unreal, even weak. It is neither. It is among the world's sufferings, not separate. Shame is one of its symptoms, so it is often suffered in secret. Yet there is no need to struggle alone. Help is out there, and with time, effort and patience, it works.
Catherine Paver Writer and part-time English teacher.