You've got my sympathy. I've had similar issues on/off with my son. He's 2e/pg.
He displayed similar psychosomatic symptoms when he was 5-yrs-old and a school that was a mismatch for him too. We withdrew him from that school and put him in another school. A similar situation occurred there too, though not nearly as severe. This year with homeschooling, it's been better. However, lately, I'm hearing that there's no one like me around, no one has the same interests, etc. Sigh.
I've been trying to get an answer to this question too for our ds 7.5-yr-old. From what I understand, it's not uncommon for eg/pg kids to have these issues. I would try to find material that deeply engages her. This is easier said than done, I know, but if your daughter can latch on to music or something that tickles her fancy - the situation will probably improve. With my son, I know if he's deeply engaged in something, then he's usually happier.
These periods seem to be more intense when they're going through a big development. Of course, learning to read is a HUGE development. Give her more advanced work and see what happens. Perhaps she needs more mental stimulation offered to her.
