Shez, I don't think it would be the Crinone. Forgive me for not remembering the date of your epu, but it was only a few days ago wasn't it? Did you have a general a-word? If so, it's more than likely that which has caused this. Even though it's only light, a-words can affect different people in different ways. I've had the dizziness and light headedness but never the pounding headache. Remember, this is a very emotional journey so even if you're feeling positive, calm and not consciously worrying, it's still a lot of pressure in your headspace and your body physically.
Take it easy OK?
Sue
edited to add definition of a-word (I forget not everyone understands my shortspeak). a-word = me being too lazy to focus on how to spell anaesthetic even though I just did. #-o