18 DPO... 5 days into missed period

Ashley β€’ IVF cycle 1 (fresh) fail: cycle 2 (frozen) MMC πŸ‘ΌπŸΌπŸ’™: cycle 3 (frozen) fail: cycle 4 (frozen) fail: ERA transfer #5(frozen) TWIN MAMA 2021!!!!

So I'm 18DPO and 5 days into when AF but no show I took a test and it's negative... has this happened to anyone and was it positive or just late AF...