I recently went to Costco and as I was getting ready to stand in line, I slipped on some chicken grease that was all over the floor. I used the palm of my hand to save myself from hitting my head and so I bruised my lower back/tailbone area. It didn't hurt much the first night, but now when I go for my daily walks, my lower back gives me lots of pain and I have to take advil to relieve the pain. As for the palm of my hand, it only hurts when I press hard. It feels like my bone might be bruised. I did go to 1st Aid when I was still in Costco that night and they put a splint on my hand and reported the injury. Would this be worth suing, or should I just try to settle with them directly?