Symmetrical painting/sketch in photoshop

Hello everyone, i am here to share another one of my sketchy digital painting with you all. i have done another one of this a few days ago. That one was a male portrait and this one is a female portrait.
This is drawn in a way as though i was holding an ink pen, the advantage was that i could choose color.
So all the slightly blended shadings are close colors with full opacity like a pen.

Here are some process shots: