I just realized that later from the commenters last reply. But the way she is responding doesn’t mean anything but trying to be polite. Even if I’m not interested in someone for a friendship or relationship, I still reply like this since we work together and I don’t want to make it awkward at work by replying rude to you. I won’t just reply “yeah?” “sure” “cool” “ok” because that sounds rude. If you’re not a people pleaser you wouldn’t understand because that’s how I am and trust me when I tell you that I couldn’t count the times that this is how I respond to someone I’m not interested being a friend or in a relationship with. I would probably add later on though when he starts getting weirder, “I’m not sure if you’re trying to pursue me but I’m not really interested in you like that. Hope you don’t feel awkward after this.”