This is a typical whiny teenager attitude, and if you want to be taken seriously anywhere, but especially here, then you're going to have to change it. Why would you take advice about how rocks look from someone if they're wrong? Is it because you couldn't find any pictures of rocks? Here is a surefire way to find pictures of rocks on google:
1 - go to google.com
2 - click on images button to do an image search
3 - type the word "rocks"
4 - press "search"
5 - view the tens of thousands of images of rocks that google just gave you
You've got a very good start on your rocks, and really in pixel art in general; better than when i started, that's for sure. But the easiest, fastest way to waste a good start is to ignore great advice, and make bullshit claims about "oh i can't do this, i can't use google, i can't find rocks." Grow up a little bit, and if YOU can't figure out how to find some friggin rocks on GOOGLE of all places, then grab your sketchpad and pencil and go outdoors to draw some REAL LIFE rocks. There are lots of ways to LEARN - the only way to not learn is to not try.