My young daughter noticed yesterday that I have a mark on my foot. I've never noticed it before, it's about 1cm in diameter. It only looks red in the picture as I was trying to pop it. It's symmetrical, has shades of different colour to it, doesn't itch at all. I'm hoping it's a blood blister but it doesn't look or feel like that. I'm just concerned as I'm pretty sure it's a large mole and it's appeared almost from nowhere. Should I be concerned? Sorry about my gross feet!