Replying to Dizziness

People that get dizzy during skiing, is it everyone? Most people? A select few? I'm not really talking 1's or 3's, but bigger tricks...and last season this was not a problem. I have noticed over the summer on my trampoline when I flip\spin I get a huge headache and very very dizzy, and when I bouncy up and down I feel my brain shaking I guess. And I'm not sure what I could have done and how to cure it but its really annoying and I have to take 5 min breaks after doing a couple tricks......this thread is basically for cures for dizziness and prevention. tl;dr tell me ways to prevent dizziness\cures