All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
The Muslim jurists stated that among the conditions of the suckling of a baby from other than his mother is that his guardian has to give his permission for this as he is the legal guardian of the baby's interests and benefits because it could be that the suckling would harm the baby. Therefore, you should not have done this act without the permission of the guardians of this baby. However, since none of the children suckled from you then there is no harm on you and do not return to this act again as long as suckling would not be an obligation as a means to save the baby's life, as this is the only time when it becomes permissible to breastfeed him without the permission of his guardian. The mothers of the babies that you have mentioned have no right to know about what you had tried to do (so do not worry!).
Allaah knows best.