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, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
There is nothing wrong with what you did. Rather, it is sound behavior since you cannot spend your mother’s money except with her permission. The Messenger of Allaah, sallallaahu ‘alayhi wa sallam, said: “It is not permissible to consume any Muslim’s wealth except with his consent.” [At-Tirmithi]. This ruling is applicable if it is a deposit or if your mother entrusted you to deal in a specific transaction. However, if it is a loan, then you may spend it as you like.
Allaah Knows best.