my girlfriend an i had protected sex on the 16 of march. her period was suppose to be on the 19 or 18 of march , on the 20 of march she started spotting instead of having a period. she has also been showing signs of pregnancy such as bloating , tender breast , sleeping a lot , and cramps from time to time.
she has already taken a pregnancy home test which was negative , she and i agreed on taken a blood test but not sure as too how long to wait after a missed period please help thanks.