Hi, what are the symptoms of nail psoriasis and can one of the symptoms be melanoychia and splinter hemorrhages ?

Mostly no symptoms. Symptoms are things you feel or experience. Signs are what you likely mean. Signs are things that can be seen one exam usually. Google nail disease in psoriasis and look at images. See if you can match yours with what they show. Better yet have someone who knows what they are doing look at them. Send us pictures when you can do this.