Sometimes when i wake up at night and go toilet i spit blood from the roof of my mouth. it's stops after a few sucks and spits. then i rinse my mouth.

Oral Bleeding: Most likely from periodontal (gum) disease but could be from a host of other possibilities, some of which can be very serious. See your own dentist for a complete and thorough oral, dental and soft tissue examination. Your dentist may refer you to your primary care physician if there is no obvious cause of your nocturnal bleeding.