Hello, I suspect that due to the crack, your tissue has been cut or inflamed tissue surrounds the tooth. This tissue may be unhealthy enough that it bleeds easily. If you have an infected tooth, there may be a fistula which is draining and responds to the action you describe. You may rinse with warm salt water and take anti-inflammatory medication such as Tylenol or Advil until you have your appointment tomorrow. Your dentist will evaluate your broken tooth and discuss treatment possibilities. A filling may be an option if the tooth is not infected or severely broken. Make sure to avoid chewing on the broken tooth. Thank you for your inquiry.