Dear PSI thapa,
Since you are a student of Class 12,you may very well know that the IIT-JEE 2013 is fast approaching and you have only limited amount of time remaining. All you can do now is to revise a lot and revise all those notes that you have taken for so long and take multiple mock tests. 
Take a mock Exam and see where you stand among the competitors and this way you can improve yourself and score much better in IIT-JEE 2013.
Getting into an IIT is not an easy task,it takes everything from an individual. If you are dedicated and motivated to get into an IIT then you certainly can. I reckon you take a mock test to see where you stand and then go about it .
 
I will always be here to help you so kidly post your queries here in the discussion board and I will get back to them as soon as I can.
 

Hope this helped you immensely..!
All the Very Best & Good Luck to you ..!!
 
Best Regards,
AskIITians Expert,
Godfrey Classic Prince
IIT-M
Please approve my answer if you liked it by clicking on "Yes" given below..!!