My cat was spayed according to the paperwork but she's acting like she's in heat?

Hi all,

I've had a bonded pair for a few months, about 3 months, and one of my little kitties (both are 2 years old), Morrigan, is spayed according to the paperwork but acting like she's in heat. She's very affectionate (more than usual), yowling and meowing more than she's ever done and seems in some sort of discomfort (agitated and restless). My vet doesn't open till Monday. I feel distressed myself but I'm commited to taking her to the vet on Monday to get looked at. I tried catnip, I turned on Cat TV of birds and mice, she isn't settling. What can I do? Debating buying Feliway plug-ins for all the rooms rn.