Your parents sound pretty responsible compared to mine. I had one talk, well two really, but the first talk came after puberty and it went like this, "You know you can get pregnant now, right?" "Yes." "Okay." The end. The second comment came when she claimed she waited until marriage which was absolutely a lie. That was it.
My girls are in Kindergarten and 1st grade and I started that type of stuff from birth just by using the correct terminology and each year I add a little more and a little more. We're nowhere near the full blown talk, but I hope to accomplish what your mom did versus mine. Mine was the shame-er---she grew up in a very Catholic household so it made sense---but she would rather slap you across your face and make you drink soap than she would talk about it.
If you find that you can't talk to your parents find a responsible adult that you can go to. My sister is 12 years older than me so I found guidance from her, but since I don't think you have that turn to an aunt, guidance counselor, teacher...etc. Someone in your life will talk to you about it.
I think a lot of kids don't really know what they know. I hear so many questionable things out of kids who really shouldn't even be experimenting with what they're saying, but if you ask them what they're saying they don't know the answer to your question. I think the media is one part of it, but kids with access to the web and YouTube is an even bigger issue!