I am devistated 😭

I went to the dr today for the first visit and they did an ultra sound, nothing was there not even a sack they did blood work and I'm due to go back in for more blood work on Monday so I would know if everything was running smoothly by Tuesday I pray that everything goes good and my hcg levels go up I really want this baby, I've prayed like no other I'm barely 4 weeks is this normal for being only 4 weeks??? I would hate to think that I'm going to miscarry 😭