Hi Naveen,

I can understand your nightmare but you yourself know that it is not possible to change your quota now. But still I suggest you to go to the official website and take the helpline number to talk directly to the concerned authorities and see if they can do anything to help you. 

Other than that, I advise that you forget about it for time being and focus on your preparation. You can still get a good college with general quota if you prepare hard enough. 

My best wishes:)