I've heard many people on this board state they have been bitten by a sea urchin. I wouldn't mind a bit of info on this. Do I need to bring anything for these bites? Do they hurt? How did you get bitten? Are they hard to see in the water? What other kinds of "sea creatures" are out there?

I keep picturing myself floating on the calm water and then I read these things and wonder if I will truly be able to relax. Seems silly, doesn't it? I hate spiders too.