TTC baby #5

My last AF was October 20-26. My husband and I did the deed October 28, November 2nd (day before ovulation day according to the app) November 6th, and November 14th. I was due for AF on Nov 17-23 and nothing. I am now 12 days late and all my test have been negative. I am waiting to be able to set up an appointment to get blood drawn BUT, has anyone else dealt with this? I know ovulation day on app isn't exact so could I have possibly ovulated later ? I been cramping on and off since the 17th of November. I did have a loss in May of this year so AF has been between 5 to 6 rather than my normal 7 days but I haven't missed a period since my MC until this cycle.