hello and welcome to hcm forum Sandra,
i would be glad to inform you that a tongue has numerous veins on its inner surface and if in case there is some kind of selling/lump, then that needs to be checked clinically by your dentist
you have not mentioned whether you have pain or not, or even infection.
swollen veins are associated with a number of factors; infections, salivary gland
i would recommend you to visit your dentist soon.
i hope i answered your query,
i wish you good health,