I have had ingrown toe nails for as long as I can remember. I do not take my toes to the doctor. The only thing I have ever done that worked is to file down the thickness of the nail, on the part where it is ingrown. I use an emery board to do this. Once, I filed it too thin, and quite a bit was actually gone. When it finally grew back, it was almost normal !! I have also gotten temporary relief by jamming a small piece of cotton under the part of the nail where it in ingrown. I shove the cotton under there with a tooth pick at night, sleep with it, and take it out in the morning. I cut my toenails straight across and I do not cut them short...if I do cut them short, I will get a bad ingrown one for sure.
What does not work for me is to cut the nail in the part where it is ingrown. For me, it just digs in deeper when it grows back. It is tempting to do, because it does bring relief at that time. But the pain that comes when the thing grows back is not worth it.