Hi snowchickie!
Sorry to hear your migraines are playing up. Not fun!
I don't get them myself, but do know for sure (as a pharmacist) that Panadol, Panadeine, Panadeine 15 (higher amount of Codeine than reg Pandeine, but not as much as Panadeine Ft), Panadeine Forte, and Mersyndol Night Strength are all Category A in Pregnancy. Category A drugs are the safest to use in pregnancy. They are those drugs "which have been taken by a large number of pregnant women without any increase in the frequency of malformations or other direct or indirect harmful effects on the fetus having been observed" (just quoting from the Royal Women's Hospital Drugs and Pregnancy book).
Panadeine Forte is the strongest out of those I've listed, but yes you do need a script from your doc. If you would prefer not to have to visit your GP, then Mersyndol is probably the best out of these, and for many, works just as well as Panad Ft. It's available over the counter at yor pharmacy. Only prob is it will probably cause drowsiness (as will Panad Ft / Panad 15), and anything with codeine in it (all listed apart from Panadol) may lead to constipation (usually only if taken for a good few days, but then in Pgcy, only a few doses, may back you up). Hope that helps hun. Ofcourse, see your GP if you are really having no luck.

As an alternative to drug therapy, a couple of things I've heard great reports from are:
-essential oils (lavendar)dabbed on your temples, back of neck, and pillow case. Also in burner.
-ice packs on face/head, and back of neck
-accupuncture
-plenty of water / gatorade
-1 cup of coffee / coke (the caffeine can help, but keep to a minimum)

I really hope you get some relief soon.
Best of luck,

Arielle