First ultrasound date?

I got 4 positives a little over a week ago. Called to schedule a confirmation the next day, the office said they don't do confirmations until 8-12 weeks...my periods are very irregular (last cycle was 55 days). How likely is it I will get an ultrasound to date the pregnancy during this first appointment? Also, is 8-12 weeks too long to wait before having my first appointment?