Thank you for your patience. There are a few things that could be going on with this eye and you will need to keep watch of this issue closely for the next couple of days. If only one eye is affected, then the chance of a foreign body in the eye, a scratch to the cornea, or an ulcer is more likely than an allergic issue. Generally allergic issues (conjunctivitis typically) occur in both eyes rather than just one.
If this was a foreign body or scratch to the eye, then the issue really would need to be seen first thing tomorrow when your vet is open. If your girl is pawing at the eye, or just seems very uncomfortable, then I would definitely encourage you to get her seen tomorrow at the latest, and if she is really painful - then get her seen at an ER vet today.
If she otherwise seems in good spirits and not in pain (as you say), then you could try some cool tea on the eye for 24 - 48 hours to see if the issue improves. The tannins in the tea can often be enough to help improve a mild conjunctivitis. Anything more serious than this and it will have little effect. To do this, just make up some fresh black tea, let it cool, then use this on some cotton wool to gently wipe the eye 3 - 4 times per day.
As above - if she becomes painful, or if the eye issue doesn't improve by the morning with some tea, then I would encourage you to take her along to your local vet to get the eye examined. It is always better to be safe and proactive with any pet eye issue. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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