8 days late, BFN, why the delay?

Leslie

I am extremely regular and I mean I never miss a month nor am I ever late. I am 7/8 days late...give or take a day depending on when exactly I was “supposed” to ovulate. Last period was 2/20 and it is now 3/28 and nothing. The ONLY thing different I did this month was take an antibiotic called Clindamycin (150 mg tablets) for about a week and a half due to a tooth infection. I didn’t even finish my bottle because they were making me feel sick and it was giving me stomach aches and whatnot.

So as usual come close to my expected period date, I was getting cramps and lower back aches and mild headaches so I prepared myself for AF. Kept pads in my purse and wore panty liners just in case. But it’s been a week and nothing. I tested this morning on an ept digital and it read “Not Pregnant”. Yes my bf and I are TTC for 3 yes now :( and my son is 9 going on 10 yrs old this year. So Idk what’s causing the delay. Should I test daily? Should I wait until next week and if it doesn’t show up then see a Dr? I hate to get my hopes up only to be sad if nothing happens. My cm is dry, and I’m cramping as if I’m about to start but nothing :( anyone experienced this or something similar before?? Any thoughts or comments are always welcome. Thank you ladies