Go for it.  You sound ready.

I find that the mothers who are most insecure, conflicted, or defensive about their choices are stay-at-home moms, work-at-home moms, part-time working moms, and full-time working moms.  Not necessarily in that order.  :-)  One way to prove you've made the best choice is to see everybody else agree with you, so your choosing another option can feel threatening to a friend who is insecure.  But your choices are neither a validation nor criticism of theirs.  I hope they can come to understand that.