I got subcision done 3 days back but still have swelling on cheeks.

Hello! Without having a photo or directly being able to assess you, it is difficult to give an exact answer, but typically swelling following that type of procedure should start to subside between the 3rd and 4th days. This is dependent upon the number of areas that were subscised, your skin type, and post-procedural care. Ice for 15 minutes every hour can help decrease swelling. If the areas are red and very tender to touch, I would advise that you schedule a wound check with the provider who performed the procedure to ensure you don't have an infection. This would be uncommon, but still something to consider if the swelling is worsening, persistent, or very painful. 

It really depends on so many factors - I usually give a guide according to the type of subcision performed. Light technique 3-4 days, but extensive subcision with say a Nokor needle can take up to 2 weeks to settle. Your specialist can guide you as the procedure performed and the recovery rate. Dr Davin Lim. Brisbane. Australia.