My grandmother suffered from heavy flows, too. When I started, she told me a few of her horror stories. She went to a game (sports). She came prepared, using primary and secondary protection. She said when she stood up at the end of the game, she felt clumps slipping out of her and overwhelming both layers of protection. She was wearing a dress and leakage didn't start until she stood up, so nothing was visible to the casual observer. However, when she looked back up the bleachers where they had been making slow progress to exit the stadium, she saw red: Red puddle ... trail of red drops ... red puddle ... trail of red drops. She was embarrassed because the red trail clearly led to her.