I would personally wait at least until AF is due before going to the doctor. My doctor actually didnt see me though. I rang him a few days after I got a BFP and asked him if I needed to come in and he said no, because he believed me and believed that the HPT was accurate!
I dont know how early morning sickness can start. For me, it started about 5.5 weeks, but I am pretty sure I have seen some people mention they had a bit of nausea pretty much immediately.
I tested 9 or 10 DPO and got a very feint positive.
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