You can only cheat if there are rules and about the only rule that could be argued as holding universally is "don't lie". Don't claim you did work you didn't do, but if you are honest about how you did it there's nothing wrong. There will of course be opinionated idiots who will complain, but that's true whatever you do.
LOTS of pro's do that exact same thing, DNP. It's not cheating at all, especially if you're under a time-constraint. For example, a lot of comic-artists use some kind of reference for poses or angles that are really out of the ordinary. It's just a matter of what you want to focus on. It could be a stepping stone to learning or you could use it when you need it if it's not a huge issue to be able to draw people from any position imaginable.
Definitely NOT cheating. It's just creating and using reference material which is totally normal and acceptable. The fact that its reference material that you're creating yourself even makes it less cheating (if its possible to cheat less than not cheating at all).
The bottom line is, if you really want to get something right, then having something to reference is a good idea. I don't tell my accountant he's cheating if he uses a calculator!
In the short time it's fine, but as others have said you're really cheating yourself. Just about anybody can copy a photo, but taking a 3d form and reducing it to only 2d is a skill that anybody that claims to be a drawer needs.
If you're going to create models in 3d, you may as well just be a 3d modeler. (Not that there's anything wrong with that, it's just a different type of art)
But, if it allows you to perfect other skills like modelling or coloring, then it's perfectly fine, just be aware when you're no longer working on other aspects.