Looks like prolapsed vent. Here is what you should do (copied and pasted from another one of my posts--apparently, prolapse is a common problem):
Soak your hen for 15-20 minutes in hot water (95-100 degrees), then dry her the best you can, put her in a enclosure, and leave her alone. Don't give her any more feed for at least six hours. Water is fine.
After she has dried a bit more on her own, you can try rubbing some honey and/or Witch Hazel on the prolapse, try to push the prolapse in once, and then don't try again for at least a day. Continuous pushing can cause the prolapse to become irritated. Make sure that the tissue is kept moist, as if it dries out, it dies. Most of the time, if left alone, prolapses will go in within 1-3 days. Make sure to keep your hen in a dark or dimly lit area, and only let her have feed once in the morning, and once in the evening. The object is to keep her from laying any more eggs, as that will only aggravate the prolapse.