Congratulations on cutting red meat out of you diet!
Seafood: Its a matter of choice. Personally speaking I do not eat any meat including seafood.
The reason why I choose not to eat seafood is this Australian study that concludes that fish feel pain, terror and fear when they are being hunted down and caught. They also have a similar nervous system to mammals and birds and have very sensitive mouths. When people fish metal hooks tear their mouths, resulting in pain.
Research has shown that fish can feel pain. According to Dr. Donald Bloom, animal welfare advisor to the British government, “Anatomically, physiologically, and biologically, the pain system in fish is virtually the same as in birds and mammals.” Fish have fully developed brains and nervous systems and very sensitive mouths. Fish use their tongues and mouths like humans use their hands—to catch or gather food, build nests, and hide their offspring from danger. Fish also experience fear. An Australian study found that when fish are chased, confined, or otherwise threatened, they react with increased heart and breathing rates and a burst of adrenaline, just as humans do.
It is this reason why I dont eat seafood. I dont want to cause harm to any animal for my benefit. It is up to you though. I know it can be hard and the cravings will come. I had cravings for meat for ages but eventually you forget what it tastes like, and then you dont miss it at all.