From your pics I would say it looks normal. The ring of gunk around the edge was left by the krasuen, which is also normal.
I can't help too much with the flavor though. I have never experienced a taste of "burnt rubber". At only 6 days it is still very green, hopefully after you get it bottled and age a bit you will be happier with the flavor.
A woman drove me to drink and I didn't even have the decency to thank her.
Kegged: Russian Imperial Stout - Belgian Dark Strong - Vanilla Mead - American/Belgian Ale