The good thing is, like you said, it's a chair and your first model. In no time you'll be making model packs.
While your getting there, you can work on scale and proportions, making even basic shapes more realistic. As you can see in the picture, If you sat in that chair your knees would be above the table. The back of the chair is too thick as are the legs, and the seat and legs should be lowered.
You already know about the texture, but soon you'll learn to map your textures and apply them to portions of the model instead of the model as a whole.
One down, one million to go, getting better with each one. I hope you enjoy seeing your finished work in a game as much as I do.
Brian.