I can't say what I saw, but NCEES is very clear about you should expect to see. Click on the SE Exam Specification links. You'll see that AASHTO content and particular AASHTO are codes specified. You can further deduce from the NCEES Exam Specification info that AASHTO only makes up a fraction of the total content you need to prepare for.Did you guys get lot of questions based on AASHTO in both morning sessions?
NCEES also sells a book they advertise as "the equivalent of an entire 16-hour STRUCTURAL exam". I didn't count up the number of AASHTO questions in the book as a total of all questions but you could do that to see if it amounts to "a lot".
I took the buildings portion of the exam, since I focus more on buildings than bridges, and I wrote above in my earlier post what I found to be far the most difficult aspect of the exam.