Regarding Income Tax Notice

Hi, Recently I received a notice from Income Tax department, which said since I did not file the return in FY 2012-13 so i need to fill compliance options on their website. My details of FY 2012-13 are as follows: 1. Salary of from Feb 2013-March 2013(since I joined in Feb 2013 only) Rs 20,000 2. Loss from Intraday equity stock trading Rs. (8,000) 3. Loss of short term capital by short term trading Rs. (100) 3. Received from and old insurance policy on maturity Rs. 25000 4. And received some money from my family for living expenses Rs 80,000 Now, my question to you are: 1.Looking at above transactions, did I fail to pay any tax or there was no tax liability for me in the said FY? 2. I did intraday equity trading, which came under speculative income but since i had loss at the end of year, so do I still need to pay tax or get my books audited? (My total turnover which is absolute sum of profits and losses in the year was around Rs. 30,000; but I don't think I had any income tax to pay at the end of year so I did not file return) 3. In the notice one important thing that I want to ask is they have given details of information, and some codes are given, it is there in the compliance section of their website also. In those codes, a few are like related to equity trading, and one is related to salary credit. But there is one code given CIB-502 which says, Contract of Rs. 10,00,000/- or more in the Commodities Exchange. But I never did any trading in commodities exchange, only equity stock exchange I did that too margin intraday or short term trading (less than 1 year). So I want to know, why is it showing the code there. If by mistake, then is it normal, how should I handle it? Kindly tell me how to deal with above questions, and the said notice? Thanks