whR's the "baNging-heAd" waLL?

hiY... few days has passed & w/ this short period, certain things tt i dreaded had "inevitably" happened... Made 2 biG stUpiD, siLLy, biG-heAd mistake in my MSM paper.. onE of it make me "jump", "scratch", "hit" like crazy when i gOt home..... almost can go & know against the wall le! Thought it's the easiest subj among my others....but who knows? this yr's paper XXX... nth to say.... jus blame myself 4 nt studying everything single thing including the "never-a-question" on Queuing-Theory.. + this yr no more direct qns anymore.. how i envy my frds, fr prev batch.. last yr qns much better than ours! Apart fr the difficult qns, i even made silly mistakes on the simple parts... Ahh tt feeling is like hard to describe... Those who experienced this will know!