So I did it. I printed my CV and letter and went to hand them in at the school. I spoke to the Deputy Head who took my CV to pass on to the headteacher, but said that probably the school is too small to give me enough experience to do the GTP there. So I'm not holding out too much hope.
The really wonderful thing is that my prayers were answered. Not the "please let this work out" ones. But the "if this isn't right, please help me to accept it" ones. Because I walked out, after what was pretty much "no" and didn't feel like a hopeless failure at getting a job. I was disappointed. But after T and I got home, he made me tea, I told him what happened, he hugged me, I decided not to get depressed and cry. If the teaching plan is right, then it will happen. (I have a few other routes to pursue.) If it's not, something else that is right will happen.
The important thing isn't that my plan broke. Having a job or a plan doesn't make you a grown-up. I have a job now. I had a job when I was sixteen - it didn't make me a grown up then and it still doesn't now. What was grown-up is that I tried even though it was scary and might not go to plan. And when it didn't go to plan, I decided to try again.
The best thing is that T knows exactly how to make me feel better. He encourages me and supports me. And he knows exactly what to say to take my mind off it...