dead in shell

Hi could somebody tell me if this egg is still viable it’s around 14 days old the air sac is tilted and there are some thin red veins and a dark spot but I can’t hear or see any movement? Thank you

This is my female cockatiel's first time having eggs. She's done a great job incubating and rolling them consistently, so I have a lot of hope. However, when I candle her eggs, I can't tell whether they're infertile or not. Her first egg was laid nine days ago. She has four eggs now, and it...