I went out the night before last wearing shoes that rubbed my foot and caused a massive open blister. I kept it clean and covered it with a plaster, which I have changed each time I have a shower. Tonight it seems to have gone really really painful and my foot is slightly swollen and it hurts to walk. Really worried about it going septic. Do I need to get medical help or just leave it to heal. Don’t mean to sound like a drama queen but really worried about it going septic. Photo attached.