Instagram - someone I'm not following is showing as mutual follower for someone else..

Hope the title makes sense. So for context, I may have semi stalked a crush, didn't like any of their photos and did not
follow them either.

However whilst searching for someone else, it says their username as a mutual follower. Even though we are not following one another.

Now I'm paranoid, is this normal. Would she somehow know I've looked up her profile ? (Don't judge, you know you do it too )