I'm answering all your questions at once.

Let me answer this one now: No, the First Amendment points to a subset of the natural laws.  

But these natural laws existed long before the First Amendment.  The First Amendment is simply pointing a handful out. 

Roe v Wade is a violation of natural law.  It's an unjust "law".  Doesn't make a difference how many judges signed off on it, it's in conflict. 

Here's the mental hierarchy to keep in mind.

Eternal Law is at the top; the mind and interior order of the mind of God.
It's not directly knowable. 

Next: Laws of nature; physics, order of nature, material laws.

Related, "the Moral Law": applied to humans, composed of "natural law" and what's called "divine positive law" (what we've been told through Scripture).

Other man made positive law...canonical law, civil law.