That's not wrong per se... although you have a lot of work to clean it up to be something usable.

You can create new UVs at any time by selecting your object and doing a different type of UV projection. I would recommend UVing just one part of your model at a time, otherwise it won't be manageable. Is it all one mesh? Typically the parts are different objects and you can UV one at a time. Hope that makes sense.