Ive been sick after blasting off a few times, never had any problem with it, but there should be some reason behing you feeling like this
Yes you might be burning yor spice, but ive gotten sick even on changa, so I ruled that one out. What I did notice after pondering the thought a while, was that the OEV's were bringing on the feeling.
My advise is to keep your eyes closed, and, make sure you not lying down, just incase you do hurl one.