Hello,
It looks like post inflammatory hyperpigmentation. Without treatment, this usually takes about 6 months to resolve and for the skin color to go back to its normal color. Topical treatments with acids and chemical peels can be effective but can take a while for the skin to totally revert to its normal color.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
It's like this http://sphotos-a.xx.fbcdn.net/hphotos-ash3/12159_574068235942962_1045008688_n.jpg