Two things I would like to offer if I may.
First, I can relate to how you feel. For my generation, spanking was a common part of parental discipline/punishment. I started to get spanked when I was about 5yo; by 10/11 it changed to the strap. All my spankings were from my father, always on the bare bottom and it continued until I finished high school at almost 18. I can't say I liked it but I can say I always knew I was in the wrong and despite being punished, I never doubted the love of my parents.
Second, I am a father of 4 and becoming a father gave me a whole new perspective. Being a parent isn't about being a best friend, not to start with. Children, and that includes teenagers, need firm guidance and a sense of accountability and consequences for actions. There is the old saying about "this is going to hurt me more than you". Until you are a parent, you can't possibly comprehend how true that is.
Provided you know deep in your heart that your mother loves you and wants the best for you and that you generally have a good relationship with her, you are in good hands. Your age alone doesn't have much to do with this. If you don't like being spanked, ask yourself what it is you do that causes the spanking and what can you do to change it.
