Help Please! Vent Irritation and Blood on Eggs

We are new chicken keepers and this is our first chicken health problem, so will be very grateful for any assistance you can provide! Made an appointment with the only local vet who sees birds (already sees our parrot) for Thurs, but hope you can recommend some steps I can take in the interim.

1) What type of bird , age and weight.
8 month old standard-size easter egger hen

2) What is the behavior, exactly.
For the past couple weeks, I noticed she had quite bit more poop drippage than the other hens on the soft feathers below her vent. Her behavior was normal, however, so I didn't think much of it and planned to clean it off one of these days. Then two days ago, I noticed a small smear of blood on the shell of her egg. When I took a closer look at her vent yesterday afternoon, I noticed not just poop but also a few streaks of blood. I also noticed she was straining to poop and nothing seemed to be coming out. Immediately we brought her inside and thoroughly cleaned her vent area with a shower sprayer. Once the poop and spots of blood were cleaned off, it looked normal. When I put her back into the yard, I didn't see her poop but didn't see her straining either; she looked clean and was pecking around the yard with the other chickens like normal. She laid another egg this afternoon, again with a bit of blood smeared on the shell. Her vent area also looks really red and moist and she seems more lethargic than the others.

3) How long has the bird been exhibiting symptoms?
Worst symptoms just the past few days. Excess poop drippage for at least a few weeks.

4) Is there any bleeding, injury, broken bones or other sign of trauma.
A few streaks of blood near vent. The area also seems generally irritated (moist, red).

5) What happened, if anything that you know of, that may have caused the situation.
No idea. Our girls are happy campers.

6) What has the bird been eating and drinking, if at all.
Blue seal organic layer feed plus whatever she finds in the yard; water from the tap. Eating and drinking both normally.

7) How does the poop look? Normal? Bloody? Runny? etc.
Haven't been able to tell

8) What has been the treatment you have administered so far?
Cleaning vent area with shower sprayer

9 ) What is your intent as far as treatment? For example, do you want to treat completely yourself, or do you need help in stabilizing the bird til you can get to a vet?
Would like to do whatever I can for her till the vet returns Thursday

10) If you have a picture of the wound or condition, please post it. It may help.
Can take one if it would be helpful

11) Describe the housing/bedding in use
Catawba-style coop with pellets. Doors are open all day and chickens free range in our fully fenced 1/4 acre yard.