Money/ Billing for appts

I don’t need numbers but if you are comfortable sharing can you please let me know how you are billed for the appts and delivery? Basically just how it works. We were told we had a bundled number for all of our appts and things required that we slowly pay and then the rest is bundled and paid at delivery. Then delivery is paid through the hospital. Now we found out we are being charged more than before. I have only had ultrasounds they told me I needed and now I’m being charged for each one (not a extra ultrasound). I was also charged for a 1st trimester screening 3 times- 1 time by the company and 2 times for different views of the ultrasound. Is it normal to be charged twice when I only laid down once for the ultrasound? I am a first time mom and just want to see if this is normal.