Bec, I have the same problem on the odd occasion.

There's no warning and nothing after. You just have a massive dizzy spell and the world seriously turns.

I had the same thing with Daniel - but in the first trimester. This time it's in the third only, so dunno.

I was just sitting watching tele the other day and the room started spinning. I thought, "Thank God I wasn't standing!" I would have gone down.