joe, i've aimed high & got my distinctions too... but end of
the day... upon graduation, i realized that paper qualifications
does not mean everything...
everyone of us don't like to regret... but let's face it as it
comes... regret is part of life... we all make mistakes and it's
about how we overcome the mistakes and become a better person (and
not necessarily achieve better results) the next time
round...
from what i sense, u're already working hard as it is... perhaps
working too hard? it's the festive seasons already...why not take a
break and enjoy the xmas/new year celebrations for a change... have
a rejuvenating recharge before the new year starts.... 
as for contribution to your research, i feel that, u've got more
than enuff at hand for u to look at... the more u wanna venture
deeper, the more lost u may get and u may not get the answers u
want end of it all...
trust me, i've been there & done that, now i'm learning things
the hard way... which means that i have to learn how to relax and
enjoy the things in life... other than studying (be it study of
work or academics)...
let's use this forum to be a support network for highly stressed
people like us, but let's not get overly engrossed and lose
ourselves... u ok with that dear joe? 