How much hCg is needed to detect pregnancy in the body. I will be turning 3 weeks tomorrow is that too early?

If incase a man and a woman gat sexual contact at the very first time, is it possible to detect pregnancy during the very first week?

How early can a home pregnancy test detect pregnancy? Which brand is the one that you can test sooner that the other brands of pregnancy test??
Thank you.

I’m about 2 weeks late & I’ve taken several home pregnancy tests, but all negatives. How early can a blood test detect pregnancy as opposed to an HPT?

Does anyone have an estimate or exact time of how long after conception a pregnancy test will detect whatever the pregnancy hormone is in your urine?

What are some pregnancy tests that are very sensitive and get an accurate result early. My period is due the 30th of this month. I was wondering how early I can take a test and it come out positive and which ones will pick up very early. Thanks!