All Dogma is doctrine, but not all doctrine is dogma: dogma is merely doctrine that has been authoritatively defined by the Church.
Here’s a snippet from the Catholic Encyclopedia’s entry on dogma: “But according to a long-standing usage a dogma is now understood to be a truth appertaining to faith or morals, revealed by God, transmitted from the Apostles in the Scriptures or by tradition, and proposed by the Church for the acceptance of the faithful. It might be described briefly as a revealed truth defined by the Church – but private revelations do not constitute dogmas, and some theologians confine the word defined to doctrines solemnly defined by the pope or by a general council, while a revealed truth becomes a dogma even when proposed by the Church through her ordinary magisterium or teaching office. A dogma therefore implies a twofold relation: to Divine revelation and to the authoritative teaching of the Church.”
Hope that helps. Remember that oftentimes doctrine is only defined when it is challenged and the Church issues a definition in response—that’s why not all doctrine is dogma.