Why is girls having sex at a young age not okay?

It's not your body so why do you care? Who are you to judge? I lost my virginty at 14 and not once have I ever regretted that, because it was with someone who means so much to me. It's a really big pet peeve of mine, when I see older girls on here talking about how these young girls shouldn't be thinking about sex or thinking about any of that stuff. But why is it that we learn safe sex in middle school?  We think about it then, right? And this generation can't be the first that's had a high teenage rate or have had a high rate of young girls participating in this activity. Yeah, it does suck that some people decide to lose their virginty early and end up regretting it, but that is their choice and something they'll learn from on their own, and when they vent on here or feel curious, they shouldn't be told that they're "too young." They should be reassured and given advice to help them with whatever it is that they're questioning. Not everyone loses their virginity when they're married, or when they're truly madly deeply in love.