Don't worry, most of us are here to help
I usually only browse the stories forum since i love to read other stories and see other writing styles... and i also like to help those in need... sure i can't spend every waking moment helping ppl improve, and i'm not the best with grammar myself (i'm getting a B in english ... and tenses piss me off) but i can usually help at least a little bit with other people's stories...
and i don't mind helping if you need it
so, good luck, and keep writing, you'll definitely get better!
Age has nothing to do with it, it all depends on practice and experience