I got bit by something on my leg kind of by my butt, and it itches really bad and now there is dark red spots all around it.. kind of looks like a rash or a bruse.. any ideas on what it could be

Could be a tick bite carrying Lyme Disease, but without seeing it, it could be anything.
Tick bites don't usually itch.

Spider bites are extremely itchy, raised red bump, and get scratched so often, become bruised. Spiders like crawling in warm clothing just taken off; laundry baskets, etc.