I had an sv* last summer and I didn't v*, but I remember I was so close to it. It was before I was truly emet so I really know what it was like, even without the anxiety.

WARNING; VIVID....

Well I had just woken up from a nap. I opened my eyes and I felt amazing! Then BAM, instant nausea. I got this tingling feeling right behind my jaw and my mouth started salivating like crazy. Then I could feel my stomach spazming just a bit and I could feel my stomach contents creeping upwards. But I held really still and I took one deep breath and held it in..... And it stopped. I didn't v* and I felt perfectly fine afterwards. But trust me, if you're going to get sick, you'll know. I knew instantly.