Why does my injury hurt more at night?

The injury is not actually worse at night - your experience of it is, and there are three boring mechanical reasons. First, stillness: during the day you move, which keeps joints lubricated and muscles warm; lying still for hours lets the injured area stiffen and swell slightly, so the first movements hurt more and even resting aches. Second, position: lying down changes what presses on what - a shoulder on the mattress, a knee twisted against a pillow, a swollen ankle left dependent - and swelling itself throbs in time with your pulse when the limb is not elevated. Third, attention: pain competes for your brain's bandwidth, and at 1am there is no competition. MedlinePlus describes acute pain from an injury as sharp and acting as a warning signal, and a quiet dark room gives that signal the whole stage. What genuinely helps: elevate the limb on a pillow to drain the day's swelling, take your evening painkiller on schedule rather than waiting for the pain to peak, use heat or ice depending on the stage (ice for fresh swelling, heat for stiffness), and do a few gentle range-of-motion movements before sleep to preempt the stiffening. The pattern that goes beyond ordinary night aching: pain that wakes you every night and does not change with position, pain getting steadily worse week on week instead of better, or bone-deep pain with fever, night sweats, or weight loss - those deserve a doctor's look rather than another pillow. Pymander is a free AI doctor, 24/7 by text, that can help you weigh yours.