7w4d today!

Kat
Hey ladies! I had my first US today (not transvaginal) and my doctor said the baby was too small for us to hear a heartbeat but she did see one and the baby is measuring at 154 bpm. Has this ever happened to Anyone else ? She also didn't draw blood work to check my HCG levels, should I have asked her to? I see alot of women posting their levels.