I am the same way after I take an exam. I guess I am just so tense during the process that after I'm done I just want to forget everything and toss back a couple of celebration...umm...."medicinal" beverages.
I truly do try to offer feedback to the forum afterwards, but it is difficult to remember exactly what was on the test. The interesting thing is, I retain quite a lot of information with each exam. I learned so much when I took the Humanities exam that I am sure will always be with me. That was my favorite one so far, as I found it so interesting.