We know it's hard to wait to discover if you are pregnant! But waiting just for a few days would be a good idea to escape any chances for false-negative results. Although many sensitive tests can detect pregnancy even before you notice a missed period, but still they limit their utilization to not being able to detect the very next day you conceive!
A recent history of a missed period and unprotected sex gives a major clue of pregnancy. Although taking pregnancy tests are a must to confirm, and they are the most reliable right from day 1 of your missed period.
How early can you detect pregnancy?
Since majorly, the first indicator of pregnancy is the missed period, pregnancy tests can be done right from the first day of a missed period. Or if you aren't sure about your next period due date, perform the test after at least 21 days of your last unprotected sex.
The pregnant women body start producing the hormone human chorionic gonadotropin (hCG) around 6 days after fertilization, so some very sensitive pregnancy tests can even detect it before you miss a period, i.e. from as early as 8 days after conception.
hCG can be tested in the urine or blood of pregnant women, any time of the day. Urine pregnancy test kits are home pregnancy testing kits that can be purchased from a pharmacy. While blood pregnancy testing being more accurate than the urine pregnancy test kits requires a visit to the pathology lab and along with yes/no detection of pregnancy also gives a measurement of hCG levels produced during that particular time, which can be further utilized by your gynecologist to determine any other complications.
Good luck to you!
1. Source Link: https://www.nhs.uk/pregnancy/trying-for-a-baby/doing-a-pregnancy-test/
2. Source Link: https://www.whattoexpect.com/getting-pregnant/fertility/putting-home-pregnancy-tests-to-the-test.aspx