SO I had my first try today at drawing a dog, here's my attempt and advice?
It certainly looks like a dog and all you need to do from here on is to continue practicing your drawing. You must learn to look at your subject for a time a notice the proportions in the head etc. Perhaps by sitting back at the distance you like to be from the subject and use your pencil to help judge the space from the eyes to say the top of the head. I assume you understand what I am referring to? Using your pencil as a measuring tool, you have probably seen artist do this by holding it out and using their thumb to mark off and judge distances. Hope this helps.
tighten up the shading. you will have to shade an area four or five times before it starts looking right. in between those shadings you will need to erase and blend to give your subject depth.