I had the same thing happen the first time I used the arc trainer (which is a very similar machine). I was fine on it, but when I stepped off, everything got quiet and it was like I was in a tunnel, I had to sit down. And I had it on the minimum settings too. In my case, it was just because I was so woefully out of shape, that thing gets your heart going more than you realize! I could only do 7 minutes at first, now I'm up to 30 mins with increased incline and resistance, and I actually love the "red devil" as my trainer calls it, because I have bad joints and it's the closest I'll ever get to a full out run.
If I keep starting over, eventually it will stick, right?
Current weight: 140
Goal weight: 135