How do you track your activity?

I'm a bit confused and I don't know what the answer is.  I had a lot of activity today!  I'm not talking just going for a walk, or going to the gym.  I'm talking physical activity for long periods of time.  It was yard clean up day at my parents house today.  My siblings and I, with our spouses and a friend of my brother, did a tonne of yard work.  Literally, 3 loads of green waste to the transfer station weighing in total a little over a tonne.

We took down dead trees, (well my brother and his friend were the ones wielding the chain saws), hauled the branches, bushes, leaves and trimmings to a trailer, loaded the trailer, took it to the transfer station and dumped it.

We arrived at my parents at 930 this morning and left at 3pm.  Although the majority of the time was spent active, there were times when I stood around waiting for the next tree to come down, or the trailer to return from the transfer station, making sandwiches for everyone and then standing around as we all ate them.

But, how do I account for the activity?  I gave myself credit for walking the equivalent of an hour at a brisk pace (pedometer has 15,435 steps on it tonight) and then I gave myself credit for gardening/hedging.  The only real thing I could find in the Weight Watcher's E-tools database. with entering those two things in the activity tracker, it came up with 15 activity points, which just so happens to coincide with my what my pedometer states I earned.

I figure this must be pretty close. Seeing as how I don't use my activity points for extra food points, it doesn't really make that big of a difference.  However I do wonder, quite often if I'm tracking my activity correctly.