Is it possible to reverse/undo tooth decay of the enamel? I have some tooth decay that has turned brown in a small spot. The dentist (didn't do an x-ray) but said it's superficial and hasn't penetrated the enamel yet, so he can't put a filling as it's too shallow.

Is it possible to treat it at home? Can it be reversed? Will it lose the brownness? 

What should I do?

It's my first tooth decay ever.

I brush (and floss!) every day most of the life, just for the past year I've been out of sync and screwed up a few times before bed.