The act of contrition as it is found in the Small Catechism of the Catholic Religion by Bishop John Neumann of the Congregation of the most holy Redeemer, Fourth Bishop of Philadelphia, Imprimatur by the Most Rev. James Gibbons, Archbishop of Baltimore, given 24 July 1884:
"O my God, I am heartily sorry for having offended Thee, and I detest all my sins, because I dread the loss of Heaven and the pains of Hell, but most of all because they offend Thee, my God, Who art all-good and deserving of all my love. I firmly resolve, with the help of Thy grace to confess my sins, to do penance and to amend my life. Amen."
Since this form of the act of contrition incorporates all the elements of the act of perfect contrition, I urge all of you, one and all, to memorize and use this act of contrition.
There are 5 qualities or elements that must be in the act of perfect contrition. Whether they are in the form of the contrition or not, they must be present. Hence, you see why I insist on the above wording, for it is flawless, and it incorporates all the 5 qualities of the act of perfect contrition. By the way, name the contrition properly. It is "an act of perfect contrition," not "a perfect act of contrition."
The 5 qualities of the act of perfect contrition are: Interior, Supernatural, Universal, Supreme, and Intense. We shall study each of these qualities.
Secondly, the act must be supernatural as to "motive." Here we have 2 motives. The inferior motive (imperfect contrition) has to do with the dread of the loss of heaven and the pains of hell. The superior motive (perfect contrition) has to do with the fact that we have offended God who is all good. Together with the sacraments of Baptism and Penance, the inferior motive (fearing the loss of heaven and the pains of hell) is sufficient for forgiveness of all sins. However, outside of those sacraments, only the superior motive (being sorry for having offended God who is all good) will suffice for the forgiveness of all sins.
We must answer this question. Just why are you sorry for your sins. Is it because drinking made you sick? That is a natural motive, and it has no relation to forgiveness. While the natural motives are good in themselves, they will never work for forgiveness.