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So last week I slept with a girlfriend of mine, she called me and said she missed her period and took a test which said she is pregnant. Is it possible to tell this with it only being a week since i slept with her?

So I've been talking to this girl for about a month and this past weekend I was out with her and stayed over her place at college. She tells me she really likes me and that I'm so cute and perfect and how she doesn't know how I don't have a gf. Her friends all like me and she says she can see us together. But last night when she was dropping me off she said she wants to take things really slow. Idk if she just wants to be sure about us or if she's playing me, idk. It's just every time I feel this way about a girl I get a feeling they don't like me, and u get sad, idk why but I do. What do you think it means when she says she wants to take it really slow?

Can anyone help me on giving a creative way to ask a girl to prom. I want to do it in person, nothing with letters in locker or anything like that. Thanks