Crushed bed bug (likely)

Usually hides in mattress seams, bed frames, furniture cracks, and other sheltered indoor crevices near sleeping people.

Blood-feeding; primarily feeds on humans, usually at night.

Flat, wingless insects that hide by day and emerge to feed; females lay eggs in protected cracks, and young nymphs also require blood meals.

Bites can cause itchy welts and distress, but bed bugs are not known to transmit disease. The image is too unclear for definitive identification; a crushed stain alone cannot confirm a bed bug.