CM & late period

Hey guys been super tired about 10 days late for period and a couple weeks back my CM was watery and stringy (normal during ovulation) but it actually “fell” (lack of better vernacular for this) out with a little pinkish brown tiny clot. I have taken 4 urine tests all negative and still no AF. Any insight would be helpful or common experiences? I’ve never been this late but all the negative tests? Nurse told me today to get a blood test from my PCP Bc even they thought for sure it would come up positive....