My face's skin problem[help please]?

Your computer monitor could be emitting ultraviolet (UV) radiation thereby causing redness on your skin. The reason you are feeling the effect only after 11:30pm could probably be due to your lowered skin tolerance late at night, caused by weakened immune system for sleeping late. Read also the importance and tips on maintaining a healthy and glowing skin. You might want to test another monitor to rule out the real cause. Change to LED monitor for best results.