I like excercise, I just don't love it

It is Friday! I just love the weekends because I love relaxing and sleeping in. I did exercise last night and I am very tired this morning. It was really hard for me to get up. I have been trying to push myself more on the treadmill because I started slower than usual to work myself up to 45 minutes. My stamina just wasn't there until now. I don't know if it is sad or not that an extra 15 minutes of exercise made me super sore and tired for a couple of weeks. I guess I would of thought an hour would do that, not 15 minutes. I guess it is whatever the body is used to. My body likes to increase at slower paces...my friend went from no activity to running 4 miles in an hour. I don't think I would or could do that, it sounds like torture. I have to say I enjoyed my workout last night and I have been enjoying it. I didn't think I could renew my interest in exercise. I had a hard time exercising 30 minutes and walking during Christmas. So weird how things wax an wane. I now have dreams of running or feel like my body just needs to move. I am sure I could stop exercising at this point but I don't want to..and that is a great thing!