Advance tax for share sale on March 31

I definitely will have to pay tax on top of what has been paid through Advance Tax. Should I pay under "Self-assessment" category?

Just for information, I have already paid more than 90% of my tax liability (even after including the long term capital gains from the shares sold on March 31st) through advance tax. 

Thanks for the clarification.By additional tax you mean penalty/interest, right?