Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain pain and irritation under tongue can be due to common causes like burning with some hot food or chemicals like concentrated mouthwash solution,
injury with some hard foods,
allergic reaction to any food or medicine etc..
Slight inflammation of vein can be due to inflammation of the overlying mucosa itself that has progressed deeper..
Nothing to worry as it is generally not descriptive of anything serious..
I would suggest you to gargle with a numbing mouthwash containing lignocaine to prevent irritation and pain..
You can also take anti-inflammatory painkiller like
Ibuprofen.
Do warm saline gargles.
Suck ice and do cool water rinses.
Take multivitamins daily..
Avoid spicy food..
In case of no improvement consult an oral physician and get evaluated..
Hope this information helps..
Thanks and regards,
Honey Nandwani Arora.