6 weeks and 5 days sac only no yolk yet

Hi Mommies! Need ko lang po thoughts nyo about this, first time mom and I’m on my 6 weeks and 5 days na po. Nag pa tvs na and sac lang nkita no yolk yet. Is this too early pa po ba na makita si baby or blighted or blighted ovum? Pero inadvise naman po ako ni doc na bumalik after 2 weeks to see if may mag change. Thank you po.