Testing 1, 2, 3, 24

[Domestic!Au with Fem!Cas] After Dean mentions the possibility of pregnancy upon finding out Cas is missing her period, Cas purchases a couple pregnancy tests to make sure she isn't. The only thing she didn't expect though, was to find out she is. When Dean arrives home from work, she tells him but it faced with a dilemma when she doesn't want a child and Dean's overjoyed.