Feeling a little scared/concerned.

Baby Azi is measuring small im at 27 weeks last Friday and she's measuring at 24- 25 weeks! They said she's looks good just small. Now I have to go in and get Doppler test every week. Doc also said could be my placenta not giving her the nutrition she needs or even a virs. I go get more blood test Thursday. Anyone else having this experience? I'm kinda freaking out hope my baby girl is okay.