Period 16 Days Late

I was on birth control for 6 years. I stopped taking my bc over a year ago. Periods were pretty normal. We’ve been ttc for 11 months today. My period is now 16 days late. I tested 2 days late, 5 days late, and 6 days late. All negatives. Haven’t tested since then because I’ve pretty much just told myself the antibiotics I was on made my period super late. Test again? Is it even worth the test at this point ?