SPUDS

I just completed my first tandem skydive this past weekend. Overall, I enjoyed the experience and I want to eventually get my license. So during the free fall I felt fine, but when the canopy opened I started to feel nauseous and thought I was going to throw up. I stayed nauseous and light headed for the next couple minutes and then I started to feel fine. I'm pretty sure I had enough water/ food beforehand. I never had a problem before with fainting or feeling nauseous, even on roller coasters. I heard that this can be caused by sensory overload for newbies, or altitude sickness. I wonder if it could also be my harness because it felt pretty tight around my legs and hard to walk in. Any input would be greatly appreciated. Thank you. Seth