Here I will show you some basics concerning faces (3DT: the digital ones).
I have already said this, but it won't heart to repeat it. On the left is a single face. And on the right you can see two faces forming a polygon. Below you can see a polygon without visible diagonal edge. Your model should be made of these.
Below is a model made out of faces. On the right is a model made out of polygons (4 square elements). Apply a mesh smooth modifier to both and you will see how the surface on the left is not as good and smooth as the surface on the model in the image on the right.
This is the same polygon from above, but seen from behind. Faces and polygons can be seen only from one side. Side that you are going to see depend on the Normals orientation. Select this polygon or just a face and flip it's Normals and orientation of the face will change to opposeside. Above you can also see a mesh made of 16 polygons. 6 polygons have their normals flipped so that you can see them if you look at this mesh from behind.
The whole point of modeling with Editable Mesh or Poly is to make a model out of the least possible number of faces (vertexes or polygons), and then to apply a Mesh Smooth modifier for the final look.
And at the end try to find some time for something besides sitting and looking at the monitor all day and night.
Here are a few exercises that you can do. First, stretch and worm up. Next three images are legs, stomach and arms exercises. Do 3 sets of each with 10 to 15 repetitions. And do not forget to stretch at the end. Or you can just go outside and run or ride a bicycle. When you're done with the workout you will feel refreshed and ready for more work.
Feedback will be greatly appreciated.