This sounds like a classic case of high blood pressure, pounding or throbbing in the abdomen and flashes of light in the eyes. The higher blood pressure and nerves could be caused by an allergic response to either something you're taking or to the candida itself, or to die-off. Be very careful with flashes of light in your vision. This can be high blood pressure affecting your retinas (the mirror at the back of the eye). Not something to take lightly as it could be a signal of an actual eye condition that should be looked at by an opthamologist. I see an opthamologist and he always says that if I ever see flashes of light I should contact him right away.