Looking at the image (last image you posted) there that's normal, you need to keep pulsing and giving the coil a squeeze together with tweezers until it glows even. You can even rub the coil lightly across the top a few times with a screwdriver (or something metal) and then pulse, it will eventually glow from the middle outwards with no hotspots. Hopefully your resistance will settle then providing, as has been discussed, it's not shorting out anywhere. (Don't squeeze or rub the coil when your firing the mod though unless you have ceramic tweezers).