Hi.. Can understand your concern.. As per your complain the lump over the cheek which you are experiencing is due to inflammation that has occurred due to injury to the soft tissues during the extraction process.. It is nothing serious as it is an inflammatory swelling and will subside gradually.. It is not a sign of infection as in case of infection there must have been pain and at times pus discharge.. You need not to worry and just follow the instructions given to you by your dentist and take the medicines on time if you are still on medicines.. You can do warm compresses over the lump as it will speed up the healing process.. Warm saline gargles can be helpful.. Hope your query is solved.. If you find the answer helpful please write a positive review and click on find this answer helpful as a token of appreciation.. Thanks and regards.. Dr.Honey Nandwani Arora..