Should I be worried?? Help 😣

So today I am 4 weeks and 4 days and when I went to get my second beta, my midwife was like "let's do an ultrasound and see how far along you are!" And I was like okay.. I thought it's too early though.

So she put it on my belly, the abdominal probe, and we saw nothing on the screen. She seemed confused and said that maybe im earlier than I thought. She did say that my uterus looked enlarged though... Idk what that's supposed to mean. :/

Now I'm extremely nervous thinking that there should have been something there, at least a sac. :( Because of the way she was acting as of she expected to see something at 4+4.

Should there be something there??? And if she had used a transvaginal ultrasound would she have seen something??? I'm so nervous now, help