Signs of 1 week pregnancy?

A few signs. Symptoms common to an early pregnancy can include breast tenderness, nausea (possibly vomiting), fatigue, and food cravings or aversions. These are in addition to a missed period.
Not many. Often early on in pregnancy some women have no new symptoms at all. Usually one of the first symptoms is nausea or "morning sickness" some women also report change in smell and/or cravings for certain foods but often no symptoms.