Hard bump on the gum of extraction site.

Have extracted my upper wisdom tooth 2 months back. I had lower jaw pain with swelling and neck pain under earlobe. Dentist says it could be because of upper WT and I removed it. I still have the same pain in the lower jaw and neck even after the removal. I am still finding answer for that.I didn't have any stiches after the WT extraction. I went for follow-up after 2 weeks of extraction and OMFS said it's healing good. Now, I noticed a small lump which is very hard on the gum of the extraction site. It's been there for 2 weeks now. It was painful if I touch or press. And sometime gives sore pain. Since I have severe pain in the lower jaw and neck, I couldn't differentiate if it's from this boil on the gum.I went yesterday to check with OS. He said, it's a bone fragment and told me to wait for 2 weeks to see how it goes. If it's painful, told me to come back to take it off.now I feel some throbbing pain there suddenly. What is shaving it off mean? will it go away on its own?