Acute Stress Disorder is diagnosed when symptoms do not last a month. If symptoms persist PTSD may be diagnosed.

Complex PTSD refers to a disorder that includes the same symptoms as PTSD, as well as additional ones. Here is a short blurb from the Veteran's Administration in the Untied States about it: Complex PTSD - PTSD: National Center for PTSD

As the blurb notes, Complex PTSD was proposed by Judith Herman. It has never been in the DSM, although the dissociative subtype of PTSD in the DSM V is a nod in the direction of Complex PTSD. Complex PTSD will be in the next World Health Organization (WHO) International Classification of Disease (ICD) manual (ICD-11).

I forgot to include in my last post the name of a website that synthesizes much of the literature on dissociative disorders from clinicians and researchers: did-research.org. It really is a great resource- just be aware that many of the menus have sub-menus and many of the sub-menus have their own sub-menus.