That aint a bad effort - the things that could be improved are pretty small as opposed to big glaring problems.
The main thing I noticed was that she has a very masculine face - which is unappealing for a woman. So I worked on softening her really strong eyebrows and bringing colour to her nose and cheeks (this is usual with caucasian women) - I tweaked small things like the chin shape (too hard and angular atm) - and I also corrected small proportional issues with the ears etc...
Looking at the rest of the unfinished painting I would question your methodology - do you have an underlying piece of line work to define the structure? It looks like you're just whacking blobs of paint on and then refining them. This is definitely the harder way to do things
Oh and if you want to watch me paint live I recently got introduced to this thing called picarto TV... It's nice to do art and share it - if you have any questions it's great to talk too! I'm painting pretty much 12 hours a day so you'll most likely find me - unless I'm eating