When is the earliest you could feel pregnancy symptoms and what could they be?

Some small changes: A woman of childbearing age who has some nausea (with or without vomiting), some fatigue (feels less energetic), a sharper/stronger sense of smell, mild soreness/swelling of her breasts, and maybe some food aversions and cravings . . . Could be pregnant. Symptoms can occur before missing a period. She can do a urine pregnancy test 1 week after missing her period, to see if she will have a baby.