Just my own two cents, but I have had the standard white leukoplakia patch under my tongue for about 5 years now. They have done a biopsy every year and always come back negative for cancer. Even though I did end up with oral cancer, the original patch had nothing to do with it. I hope your findings come back clean and if anything, this will allow you to be able to examine your mouth carefully in the future which mine allowed me to. If i hadn't been so careful about lesions in my mouth, i may have let this cancer go far too long without being attended to.

Jeff - 41yrs old/previous smoker
SCC buccal mucosa/jaw bone Stage 4
Nov '14 Partial Mandibulectomy with fibula flap, neck dissection
Jan '15 Rads x35 Cisplatin x2
Apr '15 PET/CT concerning area Follow up MRI no mass.
July '15 PET/CT 11mm nodule in right lower lobe the lung.
Oct '15 PET/CT right lung nodule 3cm mass also new left lung nodules
Nov '15 erbitux
Mar '16 CT tumors are growing again, waiting on next step
June'16 hospice had 3 Opdivo infusions trying to regain health