Why does it hurt? Is it still being rubbed by your shoes? If so, and you don't have other shoes that fit differently, you might have to wait. But, if it's not being rubbed by your shoes, can you put a bandaid or some moleskin over it for protection and then workout without pain? You certainly don't want to get it infected and put you off exercising longer, but I have good success with changing shoes/socks and covering it.