It is perfectly normal to feel resentment towards your mother at some point in your life. After all, she is the one who gave birth to you and raised you, so it's only natural that you would have some mixed feelings about her.
There are many reasons why you might start to feel resentful towards your mother. Perhaps she was always critical of you and made you feel like you could never do anything right. Or maybe she was emotionally unavailable and never really seemed to be there for you when you needed her. Whatever the reason, it's important to understand that your feelings are valid and that it's OK to express them.
If you're feeling resentful towards your mother, try to talk to her about it. Let her know how you're feeling and why. It's possible that she didn't even realize how her actions were affecting you and she'll be open to making things better. If not, then at least you'll have aired your grievances and will be able to move on with a clearer conscience.