+1 on replace the helmet. After I wrecked last year, I looked at the helmet and it looked fine. I picked it up a couple days later and discovered it was cracked through.
I think it is VERY important fo new (and returning) cyclists to wear helmets. Riding a bike isn't as much like riding a bike as you might expect. Yeah, you keep balance okay, but when you first get back in the saddle there are a lot of things going on to be conscious of. With more time in the saddle, a lot of that becomes automatic but when you first start there are a lot of things to distract you and cause an accident.
I know just what you mean with respect to the moss or slime in a puddle; there's one spot on my commute that is the same way, and it's on a curve. I've learned to take that corner pretty slow.
__________________
I stop for people / whose right of way I honor / but not for no one.
Originally Posted by
bragi 
"However, it's never a good idea to overgeneralize."