Husband watching porn!

So I just saw my husband watching porn and he know I hate it and I feel like it's cheating because when your married it should only be me he is looking at and he the only on I think like about I am so angery that I just cry out of know where but I also know it's normal for men to watch it I'm just so angery though but trying to get over it but I can't. Am I just overreacting?