Thanks all for the support! I went in this morning at 8.20am to talk to the headteacher before school about the e-mail where I confirmed with the headteacher that I couldn't do lunch duties when I worked in the morning as 8.30-1.30 was too long. He said fine and I suggested switching my Wednesday morning to Wednesday afternoon so I could do a duty then - and work 12.30-3.30.
He said fine, but stressed that at some point I had to increase my hours. I said I agreed in principle but at the moment I simply couldn't tolerate it and I felt, unfortunately, that an increase might lead to me being signed off again, and I thought some hours were better than none. So he agreed.
He then came to see me at 12 and told me I didn't look good, and that I might be taking on too much - and I told him I was leaving at 12.25, as he knew. We had another meeting when I pointed out how clear it was that I couldn't do the duties and he agreed, was very supportive, and told me to look after myself. We agreed we would look at it again after Wednesday afternoon (when I have PPA anyway so no actual teaching) and if I needed to go back to the doctor I would.
So I was pleased that he finally got it, and exhausted but pleased.
I then drove the 22 miles home, and found on my return, an email from this lunchtime from the (bitch and bully of an) Assistant Head, berating me for not turning up to do my lunch duty and not letting her know. Who know letting the Headteacher know at 8.20am wasn't good enough! Sadly, I assumed they'd communicate...
That was just too much and I broke down on the sofa - and am tempted to get myself signed off. The only reason I'm going in on the Wednesday is to do a duty to help her out, and to write a risk assessment for a trip she's leading! Gah!
Sorry for the rant...