Joint and foot pain gets me down

I went for a walk on my morning break (I usually go twice around a soft-surface track in a park across the street) and discovered a new ache deep inside my left hip. I completed my two rounds, but the ache was there the entire time--until I slowed down to walk back to the office. I'm already bothered by my right ankle and the ball of my right foot. These are both either slightly sprained or there are stress fractures, possibly the latter because these pains haven't gone away in a couple of weeks.

I'm not sure how much I weigh, as I haven't stepped on a scale in many months, but the last time I did weigh myself the number was around 220 lbs. I'll assume that I currently weigh between 225 and 230 lbs. -- according to the way my clothes fit, I haven't lost any weight but I haven't gained much, either. Whatever the actual number is, it's getting increasingly uncomfortable for me to walk long distances at a pace quick enough to get my heart pumping (i.e. not a leisurely stroll). Joint pain, especially the ankle and foot pain I mentioned above, is affecting my ability to lose weight, so I'm going to need to adjust and adapt in order to keep trying. My concern -- or strategy -- now is to add consistent weight-training several times a week, while still walking as much as I can every day. A combination of cardio and weight-training has to become a permanent part of my life. Otherwise, I'm totally screwed! With weight-training, I hope to strengthen my muscles to help ease the pressure exerted on my joints. I also hope that I will begin gaining muscle mass that will help to boost my metabolism.

Last Wednesday I joined a local YMCA so I could start using weight machines and/or free weights on a regular basis. I plan to go to the Y at least 3 times a week. Additionally, I'm going to start keeping track in a notebook (and here on this blog) of what weights and machines I'm using, of the amount of cardio exercise I'm getting, and of my progress towards getting stronger and fitter in general.