So itchy that scratching causes blood marks. What to do?
What is the cause of the itch? The best thing is not to scratch, as this makes the condition worse. You can try to calm down the area with an ice-pack as this will have a numbing effect.
We cannot really diagnose problems here - severe itchies can arise from something as simple as dry skin or an allergy, to something exotic like parasitic ascarid worms.
And Monique is right, you may have made something that may have started out insigificant into a problem by scratching the heck out of it. There are anti-itch creams like hydrocortisone, but now that you are bleeding, that's bad idea. Try a benzocaine antiseptic spray.
If it persists, see a physician.
It happens at night, after showering.
We don't diagnose things online. If it concerns you, see a doctor, please.
Separate names with a comma.