That's the front? Your front discs aren't vented? Or is the rust hiding them? I'd start over. Something's way not right. I'd have to check how pads are seated in the caliper. Don't wait, you're ruining the disc like that. Might wanna get'em turned anyway based on how that looks. What kind of pads are you using? Is the inside one doing that? Is the other side doing it too? Fronts have sliders too, make sure they move smoothly while you have pads out. Based on where you live I know salt on winter roads isn't issue but you're close to Corpus aren't you? Beach action=salty too. Check the sliders. How are the rears doing? Check it check it check it. I just did pads, rotors & lines & made sure sliders all good front & back. All of mine, inside & out, are all evenly bedded in with equal contact strips on discs.