I'd say you are coming along nicely....
For the portrait, I see quite a few "loops" in the lines, especially in the hair. This is where the stroke crosses itself forming a single point, then expanding again. For me, it's an immediate sign that you have lost control of your handles. Perhaps you did this on purpose? If so, I think it would look better without. Here is what I mean by a "loop" in the stroke...
As for the flowers, they are looking pretty good. Your shading, however, definately looks spotty. I'm seeing some linear gradients, some radial gradients and a few solid color fills as well. Also, I'm seeing some heavy stroke lines that don't really belong. To give a more realistic look, I would suggest the learning of the mesh gradient tool. It's a real bear to learn (i'm not that great with it just yet) but the results can look near photo-realistic. Also, I'm not sure what all those white spots are doing.
Please see the above comments as constructive criticism, and not an outright slam. So far I see a lot of potential, but there is ALWAYS more to learn in Illustrator.