Wow, you got a sick deal, man. $5 per bulb is a pretty ridiculous price. Well played!
On Blue light and damage to eyes:
http://www.maestrogen.com/product_detail.asp?Pid=42
These guys are using 470nm dominant wavelength LED's to illuminate silicone in a lab environment. They use amber tinted goggles, or an amber tinted lens to protect their eyes. It's no joking matter, especially how you were staring
directly into the LED's. I wouldn't worry yourself too much, what's done is done. I've even stared directly at a few panels I've made just to see "how bright it is," and it felt like I gave myself laser eye surgery. >.< But stay safe, dude, and wear shades around those Blue lights, imo. I realize you'd mostly be going in to check out your plants, but I do the same and sometimes inadvertently catch a glimpse of the LED's. For this reason I always try to put on a pair of sunglasses before going into my flower tent which has single wavelength Blue LED's inside. Inside my veg tent it's all White LED's and only ~90W so I don't worry about it.
About the black light effect. Not sure. Usually UV-A causes things to fluoresce. I wouldn't imagine there's much, if any, emitted UV-A from those LED's, but who knows. I have a remote phosphor spot light in my flower tent and without the phosphor lens it does have a very mystic looking Blue tinge to it. And oh God is it bright. I would never want to stare at 100W of 440-470nm. Hurts my brain a little just thinking about it.