@Sostenueto That sounds like a really odd parent's evening appointment. It sounds like it was really hostile. Do you think the teacher had had one bad meeting after another tonight and when she got to you, she lost her temper a bit (hence the get a tutor if you want better results comment)?
Maybe it is just me, but it is strange that the English results weren't moderated at department level. You'd think the HoD would notice if the top set were all underperforming their expectations but the 2nd top set were doing as expected.
I think the HoD has some explaining to do.