What is this red itchy rash thats been spreading over my body for 3 days?

Over the past 3 days I have had a rash thats been spreading. It started off as two little bumps on my lower back and now has spread down my butt following the crack. Its an inflamed, raised rash that is red and incredibly itchy. I have no clue what it is after looking online and nothing I've tried has worked. Also, just today, I've noticed little splotches of the same looking rash appearing on separated parts of my body. This stuff is driving me crazy and its hard to focus on anything but the itch. little help and advice would be appreciated.