The top back of my throat is red and burning and hurting i have green bloody mucus from my sinuses what is causing the red raw in my throat?

Postnasal Drip: In the context of the sinus infection, the likely cause for the discomfort and physical findings is the drainage of infected mucous draining from the back of the nose into the throat. There is also the possibility of a throat infection, pharyngitis. A number of clinical factors which can differentiate a bacterial infection from a viral one -- the former of which may benefit from antibiotics.