The P.E. teacher at the elementary school I work at has this free work out thing after school. I went to it for the first time today and I got light headed and had to walk out and collect myself for a few minutes. I have a bit of asthma and no inhaler (smart, I know). We did stuff like squats, running back and forth, kettle bell, push ups, etc.

I haven't worked out like that in a long time and whenever I do I never stick to it. I'm a very lazy person and lead a very sedentary lifestyle. I don't eat very well most of the time and yeah you catch my drift. I am overweight and not in shape at all to sum it up. How do I continue doing this without quitting or feeling like I'm going to pass out? I'd like to stick with this for once and start losing some weight and maybe get a bit toned.