Hsg test

I am newly diagnosed with PCOS and my gyno has referred me to a reproductive endocrinologist to see if they will start me on clomid since we are TTC. I called to make my appointment today and they won’t see me until my husband has a semen analysis and I have a HSG test done. They told me to call and schedule my HSG test when it’s the first day of my menstrual cycle. The only issue is I have not had a period in 6 months and that is why my gyno referred me. I’m frustrated because I don’t know when I will have one to be able to schedule it. I can’t just go to any reproductive endocrinologist because I have Tricare and they will only cover it if I go to the facility on base. I’m just looking for advice since I am newly diagnosed and still learning about it. Anyone have any advice?