Ive been spitting a little blood mixed with saliva mainly in the morning but anytime ive laid down for awhile?

Could be a number of things but my mother has had this problem and they(Dr's) can't figure out exactly how to remedy. There is a valve that in the esophagus that keeps saliva, food etc. from coming back up but it is damaged therefore the acids in the stomach tear tissue and the result is blood spit up. Surgery was one option but see a doc

Take a paper towel or Kleenex and blot it around on your gums, then under your tongue, then the roof of your mouth. then blow your nose real hard with a Kleenix, then cough into a Kleenix as hard as you can. try to see where it's coming from. Then go to the doctor or dentist. If it's your gums that the least to worry about. use a diff Kleenix for each area.

You need to see a Dr. You could have a lung problem. Do you smoke?