Araneus gemmoides CAT FACED SPIDER
My guess is that this spider you saw was either a Jumping Spider (quite possibly a Daring Jumping Spider) or a Parson Spider.
the bumps on your back is because either you have a virus or an eritation to somthing you put on your body like a new cream or somthing
the back of a spider
The spider that is black with a white crescent on its back is the Brown House Spider. This spider is often confused with the red-back spider.
I live in Golden Valley and I too found a black spider. It has the shape of a common house funnel type spider or even a grass spider. To me it looks really skinny. I just cannot get over black (charcoal) color it is all over.
A false widow spider is a spider that is known to have a skull depicted on its back. This spider also has orange legs.
A blue back spider exist.
A brown spider that has a white diamond on its back is known as a Parson spider. This spider does have a mildly venomous bite.
It can just be a red back spider...
The camel back is a cricket with spider-like legs.
Your spider is a Heartstring spider the prettiest spider ever.
An Advanced and Fast Acting Lotion for Back of head Bumps, Facial Bumps and Ingrown hairs