A few more details: Every trip I have worn CROCS Maryjanes and never had a problem. This trip the CROCS were bothering my toes a little so I switched to some sport sandals I purchased from Kohls. Very comfortable and no blisters but after a week I developed a stabbing pain in my heel - like a knife through it with every step. Any ideas? It is a little better since I am not walking as much at home but still sore - especially in the morning and after sitting a while....