I have some good news for you - I reckon you won't have to pay any CGT.
Here is the HMRC Help Sheet on this matter.
http://www.hmrc.gov.uk/helpsheets/hs283.pdf
Read it through and come back if you have further questions.
Look in particular on page 3 at 'Period of Ownership'.
You will find that the final 36 months after the property ceases to be your Principal Private Residence does NOT count against you for CGT purposes.
Whether by sheer fluke or intuition, you seem to have sold the property just within the 36 months window after you moved out.