Certain keys causing Shift to jam .

Hi , I'm using a laptop (Lenovo Ideapad y470) with Windows 7 Home Premium 32-bit. I'm not sure how I came about this problem but here it is :
Whenever I press the keys "x" or "c" on the physical keyboard , the "shift" key will act as if it's jammed . I.E pressing the letters will produce capital letters with the exception of "x" and "c" while pressing the numbers will produce the symbols instead. I've found a way to undo this effecT by pressing "shift" several times on the On-screen keyboard , but it will return every time I press the keys mentioned.
I had turned off Sticky keys and filter keys but it doesn't make any difference.
[This was typed with the onscreen keyboard.]

Any help would be greatly appreciated.

Bump !
I would seriously appreciate any form of help , guys . I'd tried most of the options on the internet such as system restore , cleaning the keyboard(I'm pretty sure it's software-related) and running ccleaner . So far , nothing helped.

Maybe it's an issue with the hardware, maybe the keyboard is damaged or something?

The chance of that seems slight as I didn't spill/drop anything near the laptop . But I'll look into it though , thanks .