Old Age.

I am afraid that this thing called "old age" has started to hit me. I have to face it that, although my mind still feels like a child, my body is taking it's toll. My knees are getting creeky everytime I get up from my single-mattress-on-the floor. Plus having a 30lb kid to carry doesn't help. Yesterday I ended up washing our two cars, nothing new, and last night my arm became extremely sore. It didn't feel like an-out-of-shape soreness. It actually was a pestering ache across my left arm and it got worse when I laid down to go to sleep. I couldn't lay in any position to alleviate the pain. I have never experienced this before. What's going to happen next? My back gives out? I have to figure out how to loose some weight. That's the bad thing about having kids, I end up gaining sympathy pounds. Sigh. Anyone know how I can motivate myself to exercise? I don't have money for fitness membership, and I had a treadmill which was a failed experiment.