Hi, I'm new here but I just had to reply to your post. I know exactly how you feel because that's exactly how I feel when I'm feeling anxious! (Which is most of the time...) But what you have just been through would definitely have raised ANYONE'S anxiety levels, so it's not surprising that you're feeling dizzy and depersonalised. Dr Claire Weeks (Book: Hope and Help for your Nerves - if you haven't read it I recommend you get hold of a copy. It's VERY old but brilliant) talks about illness and surgical procedures as being classic times when we get super stressed and are more prone to anxiety. I wish I could come and give you a hug and tell you that what you're feeling is so normal - gosh, the doctors should be telling you that!
The dizziness is because of tight scalp muscles (which will also explain the tightness in your head), and possibly also because you're breathing a bit shallow at times and getting too much oxygen in your bloodstream. I bet if you touch your forehead it tingles, or feels sore. One good exercise to relieve that is to frown, relax, frown, relax, frown, relax etc. and it till ease the tightness. Also, gently touching your chin to your chest (or at least in that general direction!!)
I've just started this program and I'm so pleased to have found it, and I hope you didn't mind me jumping in like this! But I KNOW that your symptoms are anxiety and I hope I have soothed them a bit. I really do recommend that book - or any of Claire Weeks books. You'll understand the symptoms so much better/
Hope this helps
Jools xxx