Concerned about IUI timing

I went in for CD3 stuff today. Everthing looks good.

I was originally going to do clomid 3-7, then go in on CD11 for u/s and bloodwork and then probably do trigger on cd 12 (evening) and IUI on CD14 (this is assuming that everything goes according to "plan"

So, my office is actually a satelite office of many offices - which is not a problem.

But, today the doc said the I have to do clomid on CD 5-9 and then go back to the office on CD13 for u/s and bloodwork. - this is mainly because my office is not open on the weekends.

If I trigger on the evening of CD13, there is a possibility that I could ovulate on my own with just the clomid on CD14 - right?. So if I have the IUI 36 hrs after trigger then that would be CD15, and I could have missed my window.

The nurse did not seemed worried, so I am not sure if I should be worried.

If you take clomid 5-9, instead of 3-7, maybe you ovualte later than CD14? I hope so. I would really hate to mess up my first IUI because of a timing problem.

I asked if I should bring the trigger with me on CD13. I guess if I am ready to trigger on CD13 at the appointment, then I would do so and then still have the IUI on CD14 (24 hours after trigger)

I know the RE knows what he is talking about - and I don't want to question his authority, the timing just makes me nervous.