N.H.
R.-
This time of year nosebleeds are not enirely uncommon. My little guy gets them too. However, they are not at all as you've described your son's nosebleed. It is probably nothing but would definitely see his doctor. I think it would be important to tell the doctor that he gets a headache with it. In adults that can be a sign of high blood pressure-the headaches and nosebleeds so worth checking out.
N.