Wanting a family

I am a very passionate person and my only desire growing up was to become a mom.I am 21 and married my high school sweetheart after 7 years of dating. We both have a job and a place of our own yet everyone keeps saying I'm too young and it will ruin my marriage and I'm going to miss out on so much. I really want to have my own family and I don't want to let others discourage me but is it wrong to want to be a young mom?