My husband and I had sex on cycle day 15. I'm usually 30 days total. We then waited until after the fertile window according to glow and then had sex pretty much every other day for the rest of the cycle. My period (I think) came but was really really light which is unusual for me. I'm typically really heavy day two and three but this entire period was spotting and really light. We then had sex cycle day 1 for this month. I've been super tired, really nauseous, and have had headaches. I've taken two pregnancy tests and they're both negative. Is it possible that I am pregnant and the hormones just not high enough?