Is it normal to become dizzy when you stop the treadmill/get off the treadmill?
I've JUST started exercising, really for the first time in my adult life. I'm way overweight and generally sedentary, so I'm taking it slow to start until I build a little more endurance and confidence. Right now, I'm doing 30-35 minutes on the treadmill at a time, walking at a rate of 3-3.5 miles/hr. Pathetic, I know, but it does get my heart rate up and make me sweat. I do the 4-5 minutes of "cool down" at the end, with the rate progressively lower, but no matter how much I slow down I'm still quite dizzy when I stop the treadmill and when I get off. It goes away after a few minutes, but I've gotten dizzy every time.
I'm 32 years old, not on any medications, not dehydrated, not over-caffeinated (I have coffee in the morning and I go to the gym at night), I eat before going to the gym, and I don't have high blood pressure (or any other medical problem, other than being fat). Is it normal to get dizzy like this with a treadmill? Will it go away? Should I be concerned about it?
Thanks very much for any feedback!

When I started out in September 2010 the only exercise I did was walking my dog for about 20 mins. I worked my way up to taking him to the park and walk/run. I was so out of shape (ex-smoker here), and my lungs were so shot, I could only run 30 secs, walk 2 mins and repeat for 20 min. I kept at it 6 days a week...and gradually increased my running time. Along the way, I suffered mild injury to my left knee...but took a few days off, did some reading about running injuries, took the necessary steps to prevent them in the future...and haven't stopped running since! I now run 19 miles a week!

I do know though that starting regular exercise, period, is an achievement.