oral erythematous patch

I am looking for a second/third/fourth? opinion.  I am a 24-year old healthy female nonsmoker, moderate (maybe 5 drinks/week) drinker.  I recently noticed a patch inside my cheek that has a different texture than the rest of my cheek.  I looked carefully at it under bright light, and it does show a clearly demarcated border around it, and is almost perfectly circular.  The texture is slightly smoother than the rest of my inner cheek.  The spot has been there for 2-3 weeks now, but I don't remember biting or burning this spot - although I suppose either is possible.  I also am missing a filling from a cavity I had in the molar right next to the spot on my cheek, and so I'm hoping it's just simple irritation.  I am petrified that it is erythroplakia, although it's not super bright red, just a slightly different shade than the rest of my cheek.  The Dr. I saw referred me to an ENT specialist, although the nurse practitioner who teaches one of my nursing classes said she thought it looked like I just bit it, and to wait to see if it heals.  I am a full-time student and only work part time, and currently don't have medical insurance.  What would be the chances of this spot actually being precancerous in someone as young as myself, and how long would you wait before having it checked out?  I wish I could post a picture, as I'm sure that would help.  Any assistance would be greatly appreciated!