She is pregnant or not? Pregnant or not.

We had an unprotected intercourse. I pulled out almost 5-7 mins before ejaculation. We took almost all the safety measures but eventually my partner skipped her periods dates. it was delayed for 6days After that she found a watery red spot on her underwear on 7th day For safety she took pad,n it's been 2 days since she's bleeding. The blood is not too watery but it doesn't resembles exactly like periods blood . There are some clots present but there is no characteristic odour of periods blood which she usually get. My partner took 2 pregnancy tests almost after 17-18 days of intercourse. Both were negative. Now we r unable to recognise that bleeding is just normal periods bleeding or its implantation bleeding. Whether my partner is actually pregnant or not.