As far as the weight-loss, odds are you aren't doing anything wrong at all. What you have described is quite common. There are a number of reasons for it including increasing muscle (also means more fluids in the tissues.)
Are you weighing all of your food and entering it into the Nutrition Tracker to help you keep within your calorie range? A lot of people don't do this, or don't pay attention to the numbers, if they do.
The soreness is probably from your body having been thrown in the deep end with exercise, including working in the yard. It is telling you it isn't used to this. It is really best to start with baby steps and gradually increase your exercise (the same technique applies to nutrition). You work on the initial one or two changes until your mind/body has gotten used to them, and then add a bit more to it. Are you remembering to 'warm up' and 'cool down'???? This can impact on soreness, too, if it is left out.
Are you wearing good footwear? That can make a difference, too.
Also to remember, this isn't a diet per se, but rather a healthy lifestyle.
Below are some links which may help you: www.sparkpeople.com/resource/nutrition_art
Remember this, too - even if you don't lose any weight, but eating properly and getting exercise, you are still benefiting your body in so many ways, that it is well worth continuing.