Confused....

Helen • Wife, mummy to 3 gorgeous little people and 4 miscarriages

So I'm technically 6 weeks pregnant today, did get a positive until almost 5 weeks but yesterday I did a clear blue and it came back still at 1-2 weeks. Even if I fell late in my cycle surely I should be further along? All my other tests are strong positive lines but this has panicked me. Got hcg bloods taken at drs yesterday. On the packet it did say the week indicator is not always accurate.

Has this happened to anyone else??