I slightly bleed when I sneeze

Hi. Every time I've been getting sick lately, or when my allergies kick in, I sneeze, the problem is a little bit of blood comes out as well. More so, when I sneeze on a tissue there is a little bit of blood, but I also have to spit out every time I sneeze and the spit contains a little bit of blood as well...My question is, should I be concerned, and what possible problems are causing this?

Here's some extra info: I am a non smoker, and I do not drink, I was a vegetarian for a year but for the past 6 months I've turned back to eating meat...