I think an exercise plan is better for losing weight for those of us who have some difficulty fasting. (Mouseclick makes it look so easy!) Did you lose the 10 pounds just since you started exercising? If so, great job!
I started doing workout videos over a month ago and I've only lost a couple of pounds, but I do a lot of exercises that build muscles so I don't really know how much fat I've lost. My fiance told me the other day that he can tell I lost some chin fat. I can't tell, so it was nice to hear, lol.
It sounds like you have a good plan of working your way up to faster walking. My short-term goal is just to get through my videos without feeling like I'm going to pass out, lol. My knees and ankles have especially been sore (more the ankles lately) because they aren't used to the high step I use for some exercises, but I know that soon they will toughen up and be fine.
Good luck on losing the rest of the weight, I have about 45 pounds or so to lose, so you will probably reach your goal before me. :)