Welcome! My name is***** am a 2003 graduate, and currently a Medical Director of a veterinary hospital.
I am sorry to hear about this concern.
The squinting, also known as blepharospasm, is a red flag for us. It suggests the eye may have been traumatized. So, possible ran in to something or a scratch. Other concerns would include a eye infection.
When the eye is greatly irritated, that third eyelid will often pop up as a reflex to protecting it.
No rubbing! It risks further injuring the eye. Yes, I do feel this is well worth the vet visit!
The vet will likely recommend a eye stain test to ensure the surface of the eye (cornea) is okay.Eye Stain Test for Ulcers
This simple test also helps to determine what eye medication is safe for the vet to prescribe.
Also, they may suggest some type of anti-inflammatory treatment, and even an antihistamine to help reduce that rubbing.
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