I don't know how much effort you put into doing the dog tutorial but it could really use alot more work. However, being that this is your first attempt at modeling, it's understandable for it not to look perfect, so congratulations for completing your first model. I really love the way you added a tongue to it (hehe).
If you decide to spend more time tweaking it, here's some suggestions to start with. I think lowering the back (upper back and tail area) down and rounding it off a little more will help. Also, see if you can make the toes a little shorter.
Don't be satisfied with what you can do but rather strive to do the things you can't do!
Exceed Expectations!