Why are people so quick to judge teens?

First off, I turn 19 in less than a month. I get good grades, college and HS, volunteered with autistic children, and am a huge family person. i was always described as the good innocent girl. I lost my virginity at 17 because of low self esteem, as most teenage girls have, and still lost the guy. I didn't go sleeping around with a ton of guys, just my bf at the time, who was only my second. I was on birth control everyday, and we used condoms every time. After we broke up, I found Christ and pledged no till marriage. 2 months later I found out I was pregnant. Does that make me a bad person? I don't think so. So why do people judge every young mother so harshly?