Should I seek fertility help?

I started trying to have baby number 2 thanksgiving of 2014. Still no success. Baby number 1 - my son - was conceived a mere 2 months after I got off birth control. Because we've already had a child, I keep putting off "worrying" and I know the only reason we haven't gotten pregnant yet is God's will and His will is good. How long did you try to conceive before seeking outside help?