not off to a good start

O.k. Well my goal is to start exercising. I am at 436 lbs now, so that is no easy task. I can do 25 steps at a time on the treadmill, so I decided I can do that 3x a day. It's no marathon, but gotta start someplace. So I did it yesterday fine but today, I woke up so exhausted and I've been tired all day. Haven't done any today. Really having trouble getting motivated.  I guess I just need to get my fat butt up and do it.My eating has slowed down, but I still fit in junk food. I have to lose 40 lbs for my surgery, which would have been fine but they keep moving my surgery back. Losing the weight isnt a problem, the problem is that I gain it back in a blink of an eye. I know I can do this, it's just a matter of getting my brain right. Sometimes I'm afraid to have the surgery, not because it's dangerous, but because of the food I won't be able to have. So now I am in the process of moving my thought patterns away from food and concentrating on my writing, the computer, whatever I can.