What happens if I don’t love her after sex? I felt like I was falling for her before we did the thing, it was rushed.

I think that possibly you did love her before but when you have sex with someone that you truly believe you are falling for, and you rush into something as serious as sex it can be detrimental. Sex isnt just about pleasure, it is about almost 2 people becoming one, you seeing them naked literally and figuratively. It puts you on a level of connection that goes beyond and you might not love her after because you werent fully ready to accept her, because that is love after all or possibly you mistook lust for love and you got what you wanted which was the sex and now you see no need to have conversations with her anymore.

Anything that you want can happen after sex. It is okay if you don't love her after sex. Maybe talk to her about it and tell her your reason for not loving her. Sometimes when sex is rushed, you can feel like you don't love the person, or your true feelings come to light. Before sex you could feel like you are totally in love with her, but after sex you realize that you are not really. It happens all the time. Just remember that it is normal to feel this way.