Primal can be many things, I think it's what you make of it. Some folks insist on only free-range goodies, while others (like me) do our best but still have some conventionally-raised foods hanging around. And some of us still struggle with every pound (like I do), and others lose weight effortlessly. And for some people it's a total life and philosophical transformation! Sounds like you're in the latter group.
As for stopping birth control, I'm going to STRONGLY advise against starting natural family planning if you absolutely do not want to become pregnant - yes, I know, I'm being a total jerk - without using a backup method; unless of course you don't mind the idea of getting pregnant, in which case, go for it.