You could take her to the vet as a precaution, but I have definitely experienced a jealous cat before. Thankfully, the one I was dealing with (long time ago, before my cat allergies kicked in) would just hiss at me and swerve to avoid attempted petting. They were both cats belonging to the family I babysat for, so I wouldn't think Boo would be so possessive, but man, he was!

She may eventually get over it ...