It sounds like you are ingesting to much protein. Your body can only handle around 30grams at once(I usually only take in abou 25 at once). So if you are having salmon,shrimp,and a protein drink you are overloading your stomach, which in turn can cause those exact side effects you are having!

With all that you are eating on your ride, I would have a recovery drink or a glass of chocolate milk, (you want a 3:1 ratio of carbs to protein after your ride). Wait a half hour or so and then eat some food.