Poor little fella.
Come visit the NEW QuirkyBaby website -- earn QB Bucks rewards points for purchases, reviews, referrals, and more! Free US shipping on great brands of baby slings and carriers and FREE BabyLegs or babywearing mirror on orders of $100+. Take the QB Quiz for personalized advice!
Absolutely do not fool with the foreskin. Don't pull back, don't retract. I assume you did not do any of that. Make sure no one else did or does.
Don't let the doctor pull it back when you go for a check up. I do hope it will heal on its own and you don't have to take him to the doctor, because who knows what they think needs to be done.?
Let us know in a day or two how it looks.
Here are a few links just in case:
Retraction-very good site
And this one you can print out and give to your pediatrician