When i blow my noise, blood covered mucus comes out. my noise doesn't feel too sensitive but i do have allergies often. what is it and how can i treat?

The allergies: People with uncontrolled nasal allergies may suffer nosebleeds as would be using nasal steroid for the condition especially when the spray is incorrectly directed towards the center of the nose (nasal septum). However nosebleeds can also occur in the absence of allergy. Consult your doctor to see what is needed for you- allergy treatment vs nasal cauterization.