Well, you just tried doing this again, you have to take it slower and learn how to learn again. Do "not" fall into despair about this, try to review the information that you did not absorb that came out in the end of the chapter review and find it in the chapter.

PTSD, being that it is an anxiety disorder can tend to be distracting when you don't realize it. You just need to learn how to be more focused again. Many people who struggle with PTSD will say it is hard for them to read lengthy posts even. So this could be part of what you are dealing with, you just need to keep working at it and the key here is "slowly and patiently".

((Hugs)))
OE