Your lines look pretty smooth to me, and unfortunately, Photoshop Elements lacks the vector tool. The best way I have found, with Elements, is to choose a smaller brush size and use multiple sketchy strokes, rather than trying to do a whole line in one stroke and risking a shaky hand. Then, you can go back and either make a new layer and trace over the old one with smoother lines, or go back and erase the fringes. There are some ways to use certain effects to make the line smoother, but I have had minimal success with them. If you want to work on your human facial anatomy, I recommend finding a drawing book, or online tutorial, which goes into detail about human anatomy characteristics. Half-price books and other similar resale bookstores have great options for very low prices. One of my favorite resources only cost me about three dollars there. :3

Haha, that's how I originally got Elements, too. I think it came with Elements 3 at the time, many years ago.. I've since gotten 7, as a gift. It works well enough for me :3 Some of the little things it lacks (like the vector tool) can be annoying at times, but there are ways around it. And some third parties have little add-ons that will enable the same or similar features, but I haven't really messed with them much, so I can't really give too much information about them.