I have no idea how to do that on a laptop.
But I booted with a external keyboard and problem was solved. Even though external keyboard wont work, it somehow fixed the main keyboard.
I also inverted my laptop and whacked it to remove anything stuck between the keys.
My problem is solved for the time being, but of the 2 things listed above, I dont know what worked.
The problem once reappeared after i booted without external keyboard but has booted up fine now even without the ex. keyboard.
Thanks for your help.