I have allergies so Im normally stuffed up and sucking from my nose to spit out all the mucus. Today I felt like I had to clear my throat an nose like normal but when I spit out the mucus there was like a small ball of blood looking substance in the middle of the saliva. I am very worried of what it could be, I have been a smoker for 3 to 4 years.

There could be a simple explanation but only a Dr. can examine you and make determinations.