Is my SO in denial?

So I took a pregnancy test today and there's a faint line on it but it's noticeable but my SO said that faint lines means that the test is negative because he got an degree in medical laboratory science and they alway test on pregnancy test so he knows more about it (that was his words) but I see faint lines on here all the time that's positive...and I know for sure that this has to be positive right?