Good day
It might be that you have a dry socket or infection of the socket area post extraction. This usually happens 3-5 days after an extraction and is most common in the lower jaw, due to food and other particles going into the socket area as we eat. I suggest you arrange a follow up visit with your dentist, so that the socket can be rinsed out, to allow a new blood clot to form. Most likely a script for antibiotics will also be given.