Hcg levels due dates pregnancy

Can someone help me make sense of this:

Lmp started June 30 ended July 4

SO and I had sex July 5,6,7

According to my app I ovulated July 8

I had implantation bleeding July 13

I took a blood test July 18 HCG levels were an 8

I’m supposed to retest this Wednesday

The doctor said well *technically* you’re pregnant but didn’t sound super optimistic

I’m just curious could I just have tested super early ? Technically today is day 2 of missed period ( mine were coming every 2 weeks lucky me haha)