Is This A Miscarriage When There Is No Fetal Pole Seen At 6 Weeks Of Pregnancy?

I already had one miscarriage, I conceive again I was on letrozole capsule and HCG shot....HCG was given on 14 day of period, now at 6 week of pregnancy no fetal pole is seen...... should I consider this also as a miscarriage??? Chances of pregnancy progressing only when periods were irregular but this is not in my case kindly guide me