My uncle taught me a brilliant saying. It goes like this
When I was 18, I thought I knew everything
When I was 21, I knew I knew everything
When I was 30, I knew I knew nothing.
I was told this when I was 18 and obviously in that moment, I knew everything. My uncle though, was absolutely right. Don't destroy your body just yet. You may live to regret it. If your mum says no, it is for a good reason. You have the rest of your life to live. Leave some living for later.