Grim is feeling overwhelmed and expresses his discomfort by sighing heavily, indicating that he might be on the verge of a migraine. This suggests that his current environment or situation is stressful for him. The mention of his mother implies that migraines run in the family, which adds a personal touch to his feelings.

He compares his experience to that of his mother, who frequently suffers from migraines. This comparison hints that the presence of another person in his life contributes to his discomfort, suggesting a strained relationship or a challenging social interaction. Overall, Grim's statement reflects his emotional state and the impact of those around him on his well-being.