So I have a 3 year old cat, Echo. She is spayed, and has been the only cat here since I rescued her. About a year ago strays started showing up around my house, and I've been feeding them outside. A couple weeks ago a boy cat that I've named Charlie (not neutered) ran inside my house when I opened my front door. He was friendly and cuddly, and I couldn't find an owner on my street, so I took him in and introduced him to Echo. He's been here for about 2 weeks. They chase each other around and swipe at each other whenever it gets too much for one or the other, but nothing hurtful or violent. Yesterday Charlie tried to "mate" with her and she looked at me and looked genuinely scared. I'd never seen that look before. I immediately broke it up and decided that since he won't run away that he'd be an outside cat (I'm still going to bring him inside when weather is bad, and he has plenty of food and water and also a makeshift shelter I made from a storage box and towels). Echo has been super clingy ever since that happened and I feel like something has changed.

Tl;dr- boy cat tried to fuck my girl cat, and she's acting different.

Is my girl experiencing trauma? Thanks.