Im assuming you used the smudge or blur tool when penning over the face. This is fine but there a much cleaner and consistant way to smooth over the face.
FILTER>BLUR>SURFACE BLUR is a tool that smooths out areas of similar colors (e.g. skin) while maining outlines without bluring them to much.
However if you want to be a graphic designer why are you doing image manipulating?
Another point ronnie, if you wanna be a graphic designer you really really need to stick in. In the UK there is more design students than there is jobs going. SO to get employed you have to bigger and better than the rest. THat means constant practise.
Good luck
