I'm a weeping mess!

Why is it that since becoming a mom I've become a weeping mess?! I just don't understand it. The first couple of weeks I would have blamed it on the hormones, but they should have leveled out by now. I watched a video of a little boy running to his dad, that had been gone for a while (military) and it made me cry. Even some commercials have me crying. My little girl's first laugh yesterday made me cry! I'm sitting here typing and I'm crying. I'm not sad. I'm not depressed! So what is the deal?! Have I been bitten by the crying bug? Has some monster invaded my body and its evil goal is to rid me of every tear I could possibly make?