Questions about scales (raised?) and feeding

I've been trying to find some info on this in the forum but I thought I would post here with some photos of my particular snake. I've noticed my female has a few scales that are slightly raised at the ends, but otherwise look normal (and feel smooth when I run my finger over them), as well as some slight browning on the very tip of her tail. My male had the same browning at one point, which I tried soaking in warm water with betadine in it, which did remove the brown bit but it left some raw looking bleedy skin. So I just started using some polysporin without soaking it off, and it came off with his next shed. She did not appear to have any retained shed from her last shed, and it all came off nice and clean. She is just now going into shed so hopefully the brown bit will just come off, but is this anything I can prevent? Is it scale rot? The rest of her seems fine aside from the few bent scales, which I think she just rubbed on something. Here are some photos:

http://ball-pythons.net/gallery/files/6/2/0/9/4/008.jpg

http://ball-pythons.net/gallery/files/6/2/0/9/4/010.jpg

Also, my the same female really wants to eat a lot. I'm wondering if there is anything wrong with feeding her extra. Both snakes (male and female) are right around 450 grams. Normally I would feed them one F/T rat pup (50-60g) every monday. But the last few times she has acted very hungry for a couple days before their feeding time, making the S shape with her neck every time I open her tub and acting like she's in feed mode. I know they get habituated to eating on a schedule, but I also noticed her body seemed slimmed down sooner than the males after a feed. Like he would stay kind of plump and she would look more sunken in much sooner. So last weekend I offered her a rat pup on sunday, and another one on monday. She ate them both without batting an eye and seems much more content mid week. Can I keep doing that or is that too much food for her size? I spread them out just because I thought two at once was a big meal for her size and I didn't want them getting regurgitated. Thanks for reading.

That actually looks like some shed skin was retained on the tail tip and cut off the blood supply as it dried.

This can lead to dying tissue which then comes off. I would try and keep it clean and see if it heals with the next few sheds - if it starts spreading or turning brown further up take it to a good reptile vet.

The feeding sounds fine - I often feed two smaller items if I think they are not quite ready for the next size up.

That's what I thought was on the tail tip of the male when his came off but it came off so clean on her Last shed. Her shed did come off in one piece. I'll keep doctoring it though, she's going into shed now so I expect it will come off completely.