Stupid injury... what to do?

Yesterday I sliced off a good section of the top/side of my left thumb with an exacto knife. While it's not enough to require stitches or a trip to the doctor, it is deep, ugly, and extrememly painful. It took forever to stop the bleeding.

I covered it with a bandaid a few times yesterday. Still super sensitive today.

Three questions...

1. There is some silver metallic stuff along the edge of the injury - not sure what this is, whether it's from the ruler or what. Should I worry about it for now?

2. Will the skin all grow back? I took enough off that it's noticable from the top; you can see the nice slant.

3. I'm assuming all I can do is keep it clean, treat with Neosporin, cover with bandaids, and let it air out a bit each day... right?

Boo-hoo. This sucks. I am a moron.