irritated with myself

I tried to go on the treadmill just now for 20 minutes. I didnt succeed. I could only manage 10 minutes. I’m frustrated. How will I ever lose this weight if I cant even do 20 minutes of walking on the treadmill? I should try to cut myself some slack because I also did 10 minutes this morning. But I really wanted to do 20 minutes all at once. It looks like breaking the time up is something I’ll have to do for now. Anything to get the exercise in right? I’m aiming for 5 days of 20 mins a day. Broken up in to two 10 min slots. I need to see results next thursday on the scale. I’ve been doing so good with my food and drinking water and eating healthy stuff like fruit and vegetables. Its just this exercise thats getting me. Ug.