Firstly, you need to consult your doc about that blood pressure.
The latest news suggests systolic BP of 140mmHg and above to be
considered 'hypertensive' but I think this is more an effort to be
politically correct in the face of too many people scoring Systolic
130mmHg. 
You need a doc to
run tests to conclude if it's stress-induced and not early-onset
hypertension. BTW, Singapore has more and more hypertensive peeps
diagnosed in their 20's nowadays. 
It's hard to ask you to relax and slow down in the fast-paced
Singapore society. However you do need to find a way of
destressing, be it talking it out with friends, taking some
time-off during your vacations, or whatever. Pace yourself. I know
you want to do well in your studies but you have to acknowledge
your limitations and meet your basic needs for R&R too.
EAsier said than done. In my 20's, I was a Type A at work.
And then, I became
diagnosed with early hypertension (because of hereditary factors
) and was put on
Beta Blockers which slows me down so much I can't be fast now even
if I wanted to. 
Your Diastolic BP is still decent, which suggests that it's more
likely than not to be a case of stress-induced hypertension. But I
won't take that as a conclusive diagnosis because what with
lifestyle factors and diet and hereditary factors playing a huge
role, you really can't play it too safe so go get checked
out.
Other than that, I cannot suggest anything to prevent burnout short
of a total time-off to just R&R. I was totally burnt out for
years and couldn't get out of the rut until now, and that's cause
I've physically removed myself from the lifestyle in SG and have
finally more-or-less settled down here.
Good luck in finding your own oasis amidst the tumultuous sea of
stressful living there! 
