Obviously you know that do one on the web is going to be able to tell you what is wrong. But here are at least a few things to think about, and perhaps ask our doctor about. Enlarged lymph nodes the majority of the time are a result of infections. Severe infections will not only drain to the local nodes, say your neck from an ear infection, but if untreated, progress to nodes further away (under the arm perhpas). These also become involved as your lymph system attempts to remove the debris of the infection battle. If you had an infection, it is likely that you would see an elevated white count in your blood work, as the body's immune system kicks up production to fight the infection. You haven't said how long you have been on antibiotics, and if the blood work which appeared normal, was before or after the antibiotic treatments. If it was after, the antibiotics may be working, hence the normal lab work, and the white nodule in your mouth may be non-related to an infection you had. If you still have enlarged nodes, the white nodule, etc. after several weeks of treatment, the question to ask is why? Things should resolve or significantly improve in 2-3 weeks with or without treatment. If they do not, then further diagnostic procedures are customary. If this doctor continues to chase this without results for a prolonged period of time, a referral to get a second opinion would be in order. Your history of smoking raises a red flag, and you should be more cautious than most about issue such as these. A doctor who specializes in cancer, or an oral pathologist may be your best course of action next.