Pay tax

Hello all,

I just completed my ITR 1 excel form for AY 12-13. After calculation its showing I have to pay Rs 52. I have never paid taxes myself as they are always deducted by my employer. 

So, is it late to deposit the tax now? Whts the last date for AY 12-13? and can I pay it online via challan no. 280 - (300)SELF ASSESSMENT TAX ?

Thanks