If the girl knows when guy cumed in her and it has been three weeks is to soon for pregnancy symptoms because she feels no different?

Pregnancy symptoms typically begin around six weeks after conception, so it is still too early for the girl to experience any pregnancy symptoms if she is three weeks pregnant. However, it is important to note that every woman experiences pregnancy differently, and some women may experience symptoms earlier than others. If the girl is concerned about whether or not she is pregnant, she should take a pregnancy test to confirm.