Hello and welcome to HCM.
Thanks for your query.
The presence of cold
sores on your lips and now tongue, could possibly be due to herpes
infection. Although we cannot be sure before an elaborate examination. I request you to visit a doctor at the earliest in order to rule out/diagnose an infection.
In the meantime, I would advise you against any form of oral or sexual contact with your partner.
I hope this information helps. Do write back to me for any further information.