Could I be pregnant? Late period but BFN

I'm 38 and my husband and I are ttc for baby #1. We've been good about having sex a lot around ovulation days but it's been three months since trying. Well, now I'm late by six days. I've been tired and keep feeling light cramping like af is coming. She just won't show up. I took a pregnancy test two days ago and got a BFN but just checked my CM and its thick and white (not like a yeast infection but like they say when you are early pregnancy and your cervix starts to thicken). Was the test too early? Could I still be pregnant?Could it be something else?