Referral to GI Dr, questions

In the USA here, how long did it take to get some sort of diagnosis from the GI Dr from your 1st appt?

I just cleared cardio and will be getting an appt with GI Dr to see if my issues are with my gallbladder (or pancreas) .. what does the typical appt look like? Do they do an ultrasound at that appointment or will there be more appts scheduled down the line? I'm curious generally what are the tests and how long it takes before (and if) they remove the bugger.