You need to get your foot checked out. Your situation is the definition of an emergency - a medical condition requiring immediate attention. You should notify your PCP with 24 hours of the visit and followup with them

Many Urgent Care centers will bill as if they were an ER, especially to out of network patients. I would also suggest going to a Urgent Care center that is affiliated with a hospital if possible - they tend to be better staff ed and equipped than as stand alone center