When is the soonest you can start having pregnancy symptoms and what are the soonest symptoms you can have?

Pregnancy symptoms : Symptoms of pregnancy can occur as early as the time your period was due. Early symptoms include breast tenderness, frequent urination, food aversions, fatigue, nausea.

10 days: Pregnancy symptoms can occur as soon as 10 days after conception or 3-4 weeks after the beginning of your last period. This is when the embryo implants in the uterus and the placenta starts producing the hormone HCG. Common symptoms are nausea, sensitivity to food odors, increased frequency of urination and breast tenderness. A positive pregnancy test can confirm early pregnancy.