Guilt is the most common negative emotional response to abortion. Guilt is the deep-in-your-gut feeling of having done something wrong. It is an emotion, a feeling in your body. You are especially likely to feel guilty when you have done something that harms someone else. This harm might be physical, emotional, or spiritual.
You might believe you have harmed yourself, the baby, your partner, your parents. Manuela believed she had harmed her husband because she had difficulty conceiving a child and she had lied to him.
You don't need to be punished for whatever aspect of the abortion has made you feel guilty--guilt is its own punishment. Some people believe that their religious tradition demands that they be punished for harming another or themselves. Most religious traditions actually stay away from punishment and only require a sincere request for forgiveness and some reasonable act of atonement. Atonement is an action you can take to put yourself right with your own moral code, or to put you in harmony with God, or the natural order of things.
There is a chapter on "Self-Forgiveness, Ritual, and Atonement" in Peace After Abortion to help you resolve guilt feelings.