Should my skin still have dark spots two months after treatment with liquid nitrogen? (Photo)

This is most likely due to post inflammatory hyperpigmentation. Skin lightening agents (e.g. hydroquinone) and Retina A are helpful in many. Im my patients this is used for at least 3 weeks prior to treatment and for several months after healing along with a strong sunscreen. 

Unfortunately, some people can heal with dark marks or hyperpigmentation after liquid nitrogen.  This type of reaction is impossible to predict.  In almost all cases, these marks will fade over time.  You can speed this process with the addition of a fade cream.  For this type of discoloration retinol and hydroquinone (or a combination of the two) is a good choice. 

This is a very common reaction following liquid N2, especially to the legs. Sun exposure worsens this condition.The thing that will help fade this will be-1. Time- it may take up to 6 months or even longer2. Sunscreen and sun avoidance3. Bleaching creams such as Hydroquinone4. Very very gentle treatments with a Q Switch laser- you will require at least 10 treatments. High power from a Q Switch laser can worsen this condition. Hope this helps, Dr Davin LimLaser and cosmetic dermatologistBRISBANE, Australia