Hi.. Can understand your concern.. As per your complain it seems that it is an over retained milk tooth which did not fall during its shedding time and is still present in your jaw.. In case if it is broken and if the permanent tooth has erupted behind it the best treatment is to get it extracted as it is already loose which shows that it s roots must have also resorted to some extent and if it is broken in the middle there is a definite chance that the nerves would have got exposed and will be definitely get infected and painful soon.. By the time you are seeing the dentist you can avoid very hot and very cold food items as they can trigger pain.. Take a soft diet.. You can take painkiller like Ibuprofen as it has anti inflammatory action too and will relieve pain and reduce inflammation if you have.. You can apply desensitising paste over the tooth to prevent sensitivity.. 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.. Thanks and regards..