Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain a small lump over the gums that is yellowish white in colour seems to be a GUM BOIL that can occur due to any traumatic
injury to the gum in that area by either toothbrush bristle or any had food impinging in the gum crevice leading to bacterial accumulation the area and pus accumulation leading to a lump formation..
It can also lead to some pain and tenderness..
I would suggest you to apply antibiotic ointment over it and also do warm saline gargles..
Gargle with antiseptic mouthwash..
In case if there is pain you can apply Lignocaine gel over it..
In case if it does not show any signs of improvement
consult a Dentist and get evaluated and he can do scaling of the area to remove infection followed by application of antiseptic ointment and it will help in relieving pain..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora.