My only 8 months old isa warren is very sick all of a sudden! They have been laying eggs for the last four months, albeit with a slight drop in production for the last week, but the last two days they all have laid eggs. Today, Saturday, I saw a hen stand alone with her eyes closed, her head pulled back and tail down. I could lift her without her making any resistance at all. I could see that her "rear opening" opened and closed so I thought that she had constipation, so she got a little olive oil, but I probably should not have done that because shortly after I found out that she had diarrhea, pretty watery! It would not eat or do anything. The eyes were clear with no signs of infection. What can I do to help her survive??