Welcome to Just Answer! I would like to help you and your dog with this question, but need a bit more information in order to better assist you.
No, this is not likely to be from the grass weave carpet.
What you are describing with your dog sounds like it could be an impacted and infected anal sac.
The anal sacs (or anal glands) are little glands located at the 4 o'clock and 8 o'clock position if you are standing behind your dog. They are normally about the size of a chickpea. They have a little tube leading from the anal sac to the anal opening, and what Mother Nature intended was that every time your dog defecates, a few drops of the fluid contained in these sacs gets deposited on the feces.
Sometimes, however, the little tube gets blocked and the anal sac cannot empty. Anal sac fluid is continuously produced by the body so the sac gets more and more full. Eventually it can rupture out through the skin.
Given how close the area is to fecal matter, anal sac ruptures seem to always get infected.
Treatment requires oral antibiotics since the sac is under the skin and the only way to get the antibiotics to it is by the blood stream, which means we have to give the antibiotics by mouth.
When I see patients with an anal sac abscess, I generally clean the area, start them on antibiotics and then see them back in a few days (once some of the swelling and pain have gone away) and try to express the anal gland to get rid of the blockage in the tube.
Often I have to see the patient a few times. Also, I like to see them a week or so after the antibiotics are finished to make sure the blockage (impaction) hasn't returned.
Here are some links to further information:
In terms of what you can do to help today, the most helpful thing would be for you to apply a warm compress to the area.
If you have antibacterial soap in the house (Hibitane or chlorhexidene soap would be ideal, hand soap would be ok for now) you can add a little to a cup of warm water. Put a washcloth in, then wring it out. Hold the warm, damp wash cloth to the swollen area for 10 minutes, re-warming it every 2 minutes or so. Wipe the area with a plain wet washcloth and pat dry.
Now, if you can it would be best to get in to your vet today before they close - as I am going to assume they will be closed tomorrow (New year's day). This it going to be increasingly painful for your girl as she waits to start treatment. So, if you can see a vet now, then do.
If you cannot get to a vet, and need something to help your dog sleep tonight, then when I have clients phone me after hours about this, for patients that I have seen, I advise the people that they may be able to give their dogs BENADRYL (diphenhydramine).
This should not be given if the dog has glaucoma.
I ADVISE OWNERS TO MAKE SURE IT IS PLAIN DIPHENHYDRAMINE WITH NO OTHER INGREDIENTS.
The dose that one generally gives is 1mg/lb.
Is she about 75lbs? It comes as 25 mg tablets, and if she is 75lbs, her dose should you choose to use it would be THREE TABLETS. This can be repeated every 8 hours for 24-36h.
Here is more about Benadryl:
You should see improvement (less itchy and a bit drowsy) within 30 minutes.
I do think your dog is going to need to see her veterinarian to get some antibiotics to treat this. However, if your vet is not open at the moment, then the suggestions above may help to keep her comfortable until your vet opens!
Also,in terms of dealing with the diarrhea, I would recommend that you with-hold food for 24 hours, then start back on a bland diet of 3/4 cooked white rice and 1/4 low fat protein (cooked ground beef, scrambled egg) in small and frequent amounts for about 3 days.
Best wishes and Happy New Year!
I hope that helps you.
If this has been helpful, please hit the green "Accept" button and leave feedback.
If you need more information, just click on reply and I will still be here to provide it!
The above is given for information only. Although I am a licensed veterinarian, I cannot legally prescribe medicines or diagnose your pet's condition without performing a physical exam. If you have concerns about your pet I would strongly advise contacting your regular veterinarian.