Is this normal? Flexibility?

Well, I've only done ballet once in my life and that was when I was about 4 years old but I'm 14 now which makes that about 10 years ago and I just decided about one or two months ago that I wanted to see if I could gain some flexibility so I started to stretch, (one minute stretch on each leg, back bends but I've always known how to do that,butterfly stretches, frog stretches, etc. and I wasn't very consistent but my point is I can already put my legs behind my head,lay onto my front legs, scorpion and a heel stretch and do middle splits, right and left splits and my backbend is really good so what I'm asking is how did I get flexible so fast if I've only been doing it for a couple of weeks? Am I naturally flexible?