Left temple pain with and fallowing a sinus Issue?

Sinusitis in onset stage, most likely. Very common version. Drink some water and lie on right side to allow left sinus to drain. Use mild anti-inflammatory to relive pain. Remember to continue to drink the water, to allow the mucus to thin. A glass an hour will probably do, but you'll also need to drink water when you eat, because eating uses up available water in the body. This is usually caused by thick mucus clogging the sinus, rather than the infection stage. If the above doesn't work, and you still have the condition after a few hours, see a doctor.