hi and welcome to HCM,
on the tongue suggests ulceration caused due to irritation of the tongue mucosa may be due to trauma due to sharp bite or irirtation caused by sharp cuspal edges of the premolar teeth.
Chronic Ulcerations repeatedly seen at the same area if not treated in time undergo tissue necrosis
and may progress to cancerous lesion like leukoplakia
there fore i suggest you to visit a dentist
soon and get the clinical examination done and get the diagnosis confirmed.
If it is due to premolar , selective grinding of the teeth to remove the sharp edges will help you out.
If it is a chronic area , topical applications of oral antiseptics like dentogel will give relief.
Main tain good oral hygiene
o prevent secondary infection of the ulcerated area.
i hope this helps,