Well, it’s hard to describe by text, it has a lot to do with topology and some of the rules it follows. You have to try and maintain things being all quad and evenly spaced and that is a hard thing to do sometimes. Some things I can spot:

That poly down at the front leg is very stretch and perhaps that diamond shape up top doesn’t need to be there like that. But to fix that you’d need to accommodate things all around and it would be impossible to describe here. Modeling and topology is one of those things you get better at the more you do it and the more mistakes you make the less mistakes you’ll make in the future. You have to develop that sense of how edges flow and that’s only by practice.
So if you are not happy with how the pup is going, I suggest you try what we all do and start a new file and take it from the beginning. Sounds like a crazy thought but it’s the best approach, most of the time is better to start over than to try and untangle the mess. Plus you gain speed and start to develop the sense on what’s the best approach to begin.
The more resolution you want for the shapes, the harder the mesh will be to control since there will be loops going all around. You’d want to terminate them where possible, but again, hard to explain. That thing you have there with the loop going all crazy is part of that. Don’t worry, don’t get discouraged, keep watching more modeling tutorials, get the hang of loops as you try thing over and over, and practice and practice. Feels like I’m saying lots of words but no solution, sorry.
Good thing is, the overall shape is there, you have 80% of the job done nicely, it’s just those complex things that we all struggle with that are making things frustrating possibly. Try starting over, try keeping an eye on the flow of the loops, try to keep all quads and relative same sizes, try to avoid stretched faces and crazy going loops, so try terminating them. Let me see if I can link you to a tutorial where loops get terminated.