me time

why is it when i sneak a little window shopping after gymboree and Josh falls asleep in the stroller instead of in the car, he wakes up when I try to transfer him from the car to the crib?  normally he transfers really well.  Is the difference that I picked him out of the other side of the car (since I am driving hubby's car), that it was later than I normally transfer him, or that he was truly rested?  Naps are the only time I can get some things done at the speed at which I used to before the baby was born.  Normally, I am not as productive as I would like but I am almost always more productive during naps than the rest of the day.  Today though, I have decided to let him play by himself while I brought the laptop down.  He's actually doing pretty well, not needing me to entertain him.  (of course before I was finished writing that sentence, he pulled down a basket of CDs, wii remotes, and DVDs.)  How much watching/interacting is required at this almost 2 years old age? How much is neglect?  Jared has asked me why I don't get down and play with him, though often I do.  I always felt that I wanted my children to be independent, primarily so they wouldn't cling to me so I could not feel guilty about leaving, but also because I want them to grow to be independent self assured children and adults.  I know that Josh loves me, and I think he does better in groups than other kids his age.  I guess I feel that more structured activities are a better use of my time.  I know he needs unstructured play too, but I guess I prefer him to have that on his own.  I mean, when am I supposed to have "me" time?