Dilemma, you could not afford me -I am that good!!!
What a horrble time you must have had. Here is my 2p's worth:
High temp itself does not set off convulsions, but fast rise in fever does. Give her regular Paracetamol and/or Ibuprofen 3-4x daily. A lot of kids can be quite perky in the morning and then have a quick slump in the afternoon/early evening. Yes, and plenty of fluids, always a good idea . Yoghurt/ice lollies/jelly/custard all count towards fluid intake and are useful bribes alternatives if you have a reluctant drinker on your hands.
If convulsions were to happen again make sure she is in a safe place, ie on floor or somewhere she cannot fall, remove anything hard/sharp, put her in recovery position once she has stopped. If seizing does not stop after a few minutes call 999. Hope you will not have to.
BTW, a recent study has not found any sign difference between Calpol/Brufen for Kids/both for fever lowering but I like Brufen for my kids.
Riven, as nobody is swabbing anymore, Tamiflu is now offered according to "clinical need", ie if your DD has a flu-like illness, not necessarily proven Swine Flu, and an increased risk which with special needs she may have, she could be considered for Tamiflu. As I said above, it is not a cure-all though, just bear in mind.
Hope she is ok.