Cat scared, hair standing up & won't let me pet him. Also eyes are dialated

My cat has been acting scared. He is usually very friendly but he won't let me pet him. His hair on his back is standing up and his eyes are dialated. He doesn't act like this all of the time though. It just started the last few days. I have read that cats can sense spirits and some strange things have been happening. Is it really possible? Please help.

Answer from Kate
Hi
I can't comment on whether or not cats can see spirits etc.

I do know they are very sensitive to natural occurrences and I have heard that earth tremors etc can make cats react in a fearful way. I don't know where you live but if it is America it could well be that you have had a earth tremor recently as another visitor to my site from America recently experienced a similar thing with their cat.

best wishes kate

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