Hello,For a long time now I've had what I presume to be a form of blood blister on one of my toes. It was originally formed (I think) by the nail on the adjacent toe rubbing & eventually breaking the skin. On occasions the skin has been broken (not intentionally!) and the toe bleeds profusely. Once healed, I'm left with the same blood blister, covered in quite hard skin. Why won't this heal? Note - I've had it for at least a year.Regards,Jonathan