Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns....
As per your complain it seems that along with having a salivary duct stone you also have got infection in submandibular
salivary gland leading to pus discharge that is appearing beneath the tongue as a white material..
The swelling is also occuring as there is saliva stimulation while eating and when saliva flow increases and due to obstruction it does not flow in mouth it backflows into the gland leading swelling..
I would suggest you to consult an Oral Surgeon and get evaluated and along with a clinical examination he can also advise x-ray or
MRI of the salivary gland to rule out for the location of stone and infection status..
Stone will be removed either manually if it is superficial or surgically if it is deep..
For infection antibiotics will be advised..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora..