Due date....

Quick story..

Had a misscarrage on 24th Sept...

Had spotting end of October (Dr said maybe it was my period because it lasted 5days)

8th Dec I have a positive pregnancy test clear blue which said 2-3...

If I use online due date calendar and go from 26th October when my spotting started it says I should be 6+ weeks...

Why does clear blue only say 2-3...which makes Me 4-5 weeks pregnant

I'm really confused xx