(2) The frog may symbolize the unconscious, or some part or function of the psyche that still lies buried in your unconscious, perhaps something you find horrifying or disgusting because of some traumatic experiences that gave rise to anxiety and / or guilt-feelings.
(3) Perhaps the frog in your dream comes from the story of the Frog- Prince. In the story a young woman is visited in her bed by a frog. At first, the girl is horrified and pushes the frog away. On the third night, however, she relents, and in the ensuing embrace the frog is transformed into a handsome prince.
Ernest Jones, a follower and biographer of Freud, says this is a story of a virgin overcoming her sexual fear.
For Joseph Campbell, an authority on mythology and a Jungian, the frog in the story symbolizes the unconscious, which at first sight is frightening but, when assimilated by the conscious ego, reveals itself for what it is - the total psyche, beautiful and true.
One might add that in both these interpretations what brings about the psychic transformation is a sexual embrace, but in the second
interpretation it is an inner embrace, an intermingling and mutual penetration of the masculine and feminine sides of your psyche. (For anima / animus, see Brother / Sister, section (4))