@cyberius: give it time, your brain has just had a traumatic experience (the same as when you have a major surgery), its currently fixing/realigning itself, and eventually you will feel fine and 100% yourself again. Try not to stress about how you are feeling too much, eat healthy stuff (green leafy veggies etc), sit in the sun, go for walks, don't overthink shit, take it easy on yourself - you WILL eventually feel good and strong again (most probably better than before), and you will at some point be ready to assimilate what you learnt. There is no timetable and no right/wrong - its your unique experience.
@Colourblind: beautiful post, I was so in need of those words 20 odd years ago when I was dealing with the intense aftermath of an ego-shattering trip, hopefully they will reach somebody in need in this century ;-)