Pregnancy appointment question — first time mama so please help me out

Sooo about 2 months ago I scheduled the normal yearly check up for my gyno on August 8th. I just found out I am pregnant last week and I have a trip in a few days. I won’t be getting back til the 8th.

My question is... should I call them and tell them I got a positive test? I mean I already have a gyno appointment but I don’t know if a gyno can really do an ultrasound (idk how it all works)... if I call them I’m afraid they’ll reschedule me. My husband and I already have the time off for the appointment.

Also does it show up on statements that it’s a pregnancy appointment or ultrasound? I normally pay my doctors visits with my parents credit card (it’s a courtesy they have on all of their kids).. I plan on telling them when we get back from the trip before the appointment but In case I don’t, I don’t want them to find out from a billing statement...

And lastly, do they do ultrasounds at 7 weeks? Someone told me they only do it 8 weeks and over.. but Idk what to believe

I realize this may sound like I’m a kid but I swear I’m 22.. I’m just very VERY new to this whole mothering thing and I don’t know what to do.