Sorry if this is in the wrong forum, but I really need help with my hair. For the last while my hair has been frizzy and just generally a total pain in the behind. Back when I henna'd it, it seemed to be thicker and shinier, but I have since that time decided I want to go natural. I have semi wavy hair, and I'm not sure whether or not it's the fact that I brush my hair, or the fact that I use silicon shampoo's for my hair that's making it react this way. I've tried the no shampoo method, but it made my already greasy hair even more so. It seems I have this weird blend of too greasy/too frizzy hair. Any help would be much appreciated.

Here's a pic of when I used to henna:


Here's a recent pic a day after a shower: