The original creator of a work hold the copyright, which means that can distribute, authorize distribution, profit from and create or authorize the creation of derivative works. If you are the only creator involved in the end product, you may do whatever you want with it. The problem arises when you copy someone elses work. If Jones wrote A and B and you glued them together into a third work, you need permission from Jones to do that – the answer to "what can I do?" is implicit in your copyright assignment / license agreement. If you did not get permission, you crossed a legal line and your lawyer can advise you how to dig yourself out.
However, it also matters in what way you "took" works A and B, and what you mean by "redefine concepts". For example, if works A and B present certain ideas and you say "Aha, I can solve this if I just redefine L and M", and write a new paper based on the ideas of A and B. Ideas are not protected by copyright, so the relevant distinction is whether you copied and modified the ideas, or the expression of the ideas (the latter being protected by copyright).
Every work past A and B is a derivative work, given your description. If you rewrite a chapter enough times, it may not pass the threshold of substantial similarity, but if C is infringing, you would be liable w.r.t. that work, and possible for D as well, even if E is sufficiently different.