Ureteral stones are crystals that get stuck in the thin tube between kidney and bladder. When they move, they send out sharp, unmistakable signals.

Sudden flank pain is the headline. It feels like a knife below the ribs and shoots into the groin as the stone inches downward.

Nausea and vomiting ride along. The pain triggers a sick stomach, even though the gut is fine.

Blood appears. The urine may look pink, brown, or tea-colored, and the change can happen even when pain is mild.

Urgency and frequency climb. You race to the bathroom every few minutes, pass only drops, and feel burning like hot sauce.

Stream can stop cold. The stone acts like a plug, so urine may pause, then restart after you change position.

Late signs include fever, chills, or a swollen lower belly—an alarm that the kidney is backed up and infected.