If your Bhcg level is increasingly slowly and at 8 was still no gestational sac visible then then it's probably a missed abortion but you still can wait for another wk and have vaginal ultra sound done by a good sonolologist to get it confirmed and show it to your obstetrician . She will guide you best .
Next Steps
Vaginal USG and visit to obs n gynaecologist doctor
Health Tips
Another bhcg and USG vaginal