Capital gain (urgent)

Vishal (Others) (28 Points)

26 February 2014  
Hello Sir, I have a query on the Capital Gain, please help me to understand.
I had booked a flat (construction was not started at that time) in March 2010.
Got the Allotment letter on August, 2010.
The flat is still under construction till date and builder will give the possession in dec 2015 (Not sure). I have sold this flat on Jan 2014. I have got some appreciation on this so please let me know that the appreciation amount is under long term capital gain or short term capital gain or any other?
If this consideration is under Long term capital gain and I purchase a new flat then do I have to pay any tax on this or not?
 
Please guide me.
Thanks,
Vishal