SMALL GROWTH ON CHIN OF MY MALE RAT

Question
THERE IS A SMALL GROWTH ON MY RATS CHIN COULD THIS BE A TUMOR, PLAN TO TAKE TO VET BUT IF IT IS NOTHING OR SOMETHING I CAN CARE OR AT HOME I WOULD RATHER DO THAT.

Answer
I am getting tons of these letters about growths on rats chin and so far, the good news is that is turning out to be an abscess rather than at  tumor. Is there a crater or scab on it?  Did it appear out of nowhere?  

Let me know and we will go from there!