Thanks for sharing your concern.
your history suggests that you have developed ulceration and pigmentation on under side of your tongue and gums.
here i would suggest you to visit your dentist
as soon as possible,get a biopsy
done for the lesion under the tongue.
Also if you have any jagged tooth it is better to get that treated at this stage only.
wait for your biopsy results.
meanwhile follow very good oral hygiene
measures as it appears that you have gingivitis
if possible, it is better to get cleaning done(scaling).
please start with vitamin B FOR 15 days.
Later on after exact diagnosis treatment modalities can be planned.
hope it helps.