Bring a large pot of lightly salted water to a boil. Cook shell pasta in the boiling water, stirring occasionally until cooked through but firm to the bite, 8 minutes. Rinse in cold water until cool and drain.
Combine pasta, chicken, celery, and almonds in a large bowl. Mix mayonnaise, lemon juice, salt, and pepper in another bowl. Pour mayonnaise mixture into pasta mixture; stir well. Fold eggs into pasta. Cover and refrigerate for 6 hours.