13DPO So confused!

Jessica
I am 13DPO today and got my BFN and Glow says I am due tomorrow which is odd cause I am on CD30 which mine only ever last 28/29 days. And last time I got a BFP 13DPO but it was CD28. So confused and getting down. I have had cramps the past week also. It's our 3rd month of trying after I MMC in Aug. just want my rainbow baby!