A case of the blahs

I'm having a hell of a time getting up off my ass these days. And then I feel incredibly guilty that I haven't done anything superfantasticfun with the kids and then I feel like a horrible mom and then I want to crawl under the covers and hide. Which doesn't help with the getting up off my ass any. I don't know what is wrong. I really want to do fun things with them but I'm either lacking the energy, motivation or intelligence to come up with and execute them. I take them to the park pretty much once a week but sometimes we only stay five or ten minutes. The Weebs loved it the first few times but now spends the entire time we are there having a fit to do something else. On the slides? SWING SWING she demands. So I put her in a toddler swing, OTHER ONE OTHER ONE she insists. So we move to the next toddler swing... nope. Then I swing with her in one of the big kid swings. She wants us to swing in a different one. And on and on it goes. I end up exhausted and she seems dissatisfied every time. I've also been taking her to the library every Friday. This seems to be going well. They have puzzles she likes to do and we get half dozen new books to read each week. The girl loves her books. We easily read twenty five or thirty books a day. But still this outing only really takes about half an hour. I don't have my kids in any of the myriad of toddler classes, Gymboree, Little Gym, Kindermusik. Are they worth it? I don't know. I guess I should look into it. I've been meaning to, really. Some days it seems like I manage little more than basic house maintanance, keeping everyone fed and in clean diapers and updating twitter. Priorities people. So is it persisting PPD? Laziness? Do I need some meds, a pep talk, a drink, a nanny, a kick in the backside? Or maybe just some good ideas?