Af due 9/15 & I'm still unsure!!

❤Chloe
Ahhh so confused! AF was expected on 9/15 and I started getting spotting that day but it still hasn't turned into AF. I took a pregnancy test on Sunday morning and it was BFN. I'm trying to hold out on taking another because I think I'm out. However, with my son I spotted during my period time and didn't figure out I was pregnant until 7 weeks. Also, my bbt was 98.5 today, which is the highest its ever been. Any thoughts would bring me comfort, thanks!