Hi.. Welcome to Healthcare Magic. I have gone through your query and can understand your health concerns.. As per your complain pain after extraction is a normally finding and it can continue for about a period of a week or even more but in case if the pain has exaggerated after 6 days there is a possible chance that there in a non healing extraction socket and the condition is known as DRY SOCKET.. As you are already on antibiotics the chances of infection are less.. I would suggest you to consult your dentist and get evaluated and in case of dry socket irrigation with hydrogen peroxide, betadine and saline and placement of Zinc oxide eugenol packs which has to be changed every alternate day along with antibiotics and painkillers will provide relief.. The yellow coating on tongue can be due to fungal infection known as thrush and if it is detected by the dentist antifungal oral medicines like Fluconazole or itraconazole will help.. Nystatin mouthwashes will provide improvement.. Antifungal lozenges can be taken.. Taking more probiotics in diet like Yoghurt will help in resolution.. Hope this information helps.. If you find the answer helpful please give me a Five Star Review and click on found the answer helpful as a token of appreciation.. Thanks and regards.. Dr.Honey Nandwani Arora..