Thank you Victor..
This scratching at Skooters head is most likely become an Obsessive/Compulsive Disorder or a habit. Cats all will rub their heads against objects to transfer their smell onto this object as a territorial hereditary issue. Even though you are feeling ridges, Victor, as long as there is no hair loss or red irritated areas of the skin under the fur, this will not be harmful to him. The ridges have developed after years of rubbing and is a normal process.
You do not need to get your head examined, Victor nor do you need to get Skooter's head examined unless there appears obvious lesions that would require treatment. From what you have described to me, Victor, this is normal and harmless to Skooter.
This blood you see in the bathroom sink may be due to a Urinary TRact Infection.....when this happens to male cats, they will urinate blood in odd places and they especially like bathroom sinks so you know that he is hurting....for this, Victor, I would take Skooter to your vet...this condition can cause crystals that could block his urethra and this could be very serious.
Does that make sense to you, Victor?
Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please Reply so I can clarify for you
Sincerely, XXXXX XXXXX