I HEART 80s

Taken on its own, today's entry is quite bland.  It reveals one lazy student, hoping to get by on a wing and a prayer; but also a young man who is relatively happy with his lot.  However, knowing what I know now (and what subsequent entries will reveal), this was definitely not the case.  I guess that I must have been suffering 'exam stress' or some other student condition.  Anyway, I reckoned that I had 'no real chance of doing well in these mocks' and that I 'must try and learn something in the few days before they come up.'  Then, written with the same pen, presumably at the same time, 'college was... quite boring but no problem.'  What's the phrase?  I'm 'an enigma, wrapped up in a riddle inside a conundrum' or something similar.