Hcg <1.00 no period

So today is the day of my period but it didnt start. I have elevated body temp and a bit sore breasts, might be darker areolas but Im not sure. On 12dpo I got dark brown spotting whichI hope was implantation bleeding. Did htp-bfn, today went for a blood work-hcg <1.00

I dont know-I sonehow feel pregnant and maybe it is too soon for tests to show positive if implantation was this late (12dpo)?

Im thinking to wait for a week and if no af, make one more blood test, if result is the same, then go to visit a doctor.

Any opinions? Has something like this happened to you?