Giggle - I'm sure you'll be fine as exposure was minimal, don't stress (easier said than done I know).
WOP - Yep, colostrum. I had some the other day too. Best just to wipe it with a clean cloth not your fingers to avoid any germs or infection. Try not to play with your nipples too much... Stimulating your nipples can also bring on labour so best to leave the girls alone a good tip for 37+ weeks though!!
Giggle is right, colostrum will change to a yellow colour in the first few days after birth.. A bit like egg yolk.