Dream about blood is sadly bad luck, danger and illness. There is something missing or lacking in your life. Someone is trying to get through to you one way or another. It is a harbinger for some consciousness or problem. You need to acknowledge and express these feelings, even though it may be shameful.
Blood dream is an evidence for a situation where you are acting inappropriately. There may be a dead or decaying situation or issue in your life that you need to address. You need to turn your negative energy into something positive. The dream is a premonition for losses, suffering or negativity. You should not take things for granted, especially if they seem to come easily.
If you dreamt about blood:
It may be much easier for you to adopt a very self-righteous and grandiose attitude, but this will only serve to alienate you still further. It would be far more preferable to try and see the event from a more humorous and positive perspective.