I know it's stressful and the wait doesn't make it any better. Hopefully he's right... and it's a fibroma. I don't want to add to your stress, but just because you don't have any precursors doesn't immediately mean it's not cancer... read my signature. I'm the same as you. That said... it's likely nothing. If it is something then you've caught it early so try not to fret... rather do something to take your mind off the next 10 days... The reality is you'll know either way very soon. Don't worry now, it's done, it either isn't or it is. If it is you will deal with it. It's great you had it looked at and biopsied you are ahead of the game. If the biopsy comes back negative, just keep an eye on the area regardless. It took a few tries before they caught mine as it was hiding in my tongue, and I too had an irritating molar!
take care and welcome.. I hope you don't have to be here for long.