My fistula wound from surgery is healing weirdly! Need your advice

I had a fistulotomy in August of this year and today I checked to see how they're doing (I have 2 wounds). One of them is pink and looks like a scab you tore off and it's all pink. The other one is virtually gone, other than a little white line. I wiped it to make sure it wasn't pus and it wasn't. It doesn't hurt it's not red, it's not raised or a bump and it's not round like my other fistulas. So I'm hoping this isn't a fistula either. It's so weird because the skin is perfectly normal other than this little maybe 1centimeter long white line. Have any of you gotten this? Should I be worried? I'm going to the doctor in two weeks, but wanted to know if this has happened to any of you and if so what is it?