Ouch, poor thing... I'm prone to those as well. Not fun.
I used to just have straight-up migraines that would hit me in the back of the neck and be with me for days. Now I get the flashing lights, the nausea, the sound and light sensitivities, the pain...for days...LONG days.
I'm sorry your day on the slopes was postponed...Dang.I know you were looking forward to it.