Hello, thanks for writing in to HCM.
A painless lump in the oral cavity must not be ignored even though a lot of oral cavity growths can be benign.
A diagnosis needs a proper examination of the exact location and appearance of the lump.
A few common possibilities are a retention cyst/ranula (blocked salivary gland duct), inflammatory processes, salivary gland tumors, duct calculi etc.

I would recommend that you visit an ENT surgeon, who can examine your oral cavity, throat and neck. Treatment would be cause-specific.
Hope this is helpful.
Take care.

Hi..
Can understand your concern..

As per your complain lump under the tongue can be due to injury to a minor salivary gland or its ducts leading to spillage of mucous into the adjacent soft tissues leading to formation of a lump and the condition is known as MUCOCELE..

It can also be due to blockage of the duct of major salivary gland known as SUBMANDIBULAR SALIVARY GLAND due to crystalline deposits formed by the minerals present in the saliva..

Due to blocked duct there is back flow of saliva to the gland leading to formation of a swelling which is more evident during eating..

The ulcer can be a canker sore or caused due to trauma from any food item..

I would suggest you to consult a dentist and get evaluated for the exact cause of the lump and ulcer..

In case of mucocele it many a times ruptures itself and heals eventually but at times large mucoceles needs surgical removal or laser ablation..

In case of salivary gland duct blockage exploration and removal of the salivary stones can be helpful..

In case of canker sore or traumatic ulcer if not painful will heal by itself in a week or 10 days time..

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.