A. For pain relief you can give, if you have available, Rimadyl (Carprofen) to help with inflammation/pain. Most human drugs are dangerous to use and require an exam to say they are safe to use in this case, so I cannot recommend them.
Besides medication, it will help to apply a cold compress to the area for 5-10 minutes or as long as your pet will tolerate. There is a risk that the anal gland could rupture overnight, however giving pain meds would not prevent that from happening. Having the anal glands expressed and treated as early as possible tomorrow may be all that can be done at this point.
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