Hi Hope this message finds you in good health. I have gone through your complaints and understand your concern. Any fracture in foot can cause the whole foot to swell.Fifth metatarsal fracture definitely needs attentionIf the fracture is minor,undisplaced,plaster immobilisation should be enough. If its displaced,it may require surgical intervention. Nothing to worry about. I hope your question has been answered. If you have any follow-up queries,feel free to consult me anytime. Thanks,Take care,God bless.