What Causes Blood Rush To The Masseter Area On Bending?

If I bend at the waist and lower my head, it feels like all the blood is rushing to the masseter area (from muscle to ear) on the right side of my face. This happens on occasion, and the last day or so it has been happening. When I don't bend over, there is still a slight pain in the area, so I've been massaging it. Not sure if this is a symptom of TMJ or something else I should be aware of? Please point me in the right direction. Thank you!