Ring you vets in the morning and ask them about the test.

First time I tried to mate my bitch I missed and she wouldn't let the stud anywhere near her, it was really disappointing after all the planning I had put into it. I think it was only about day 11 or 12 but she was obviously an early one. Next time I went on day 7 and 9 and it worked, so if you have to travel it would be probably best and more cost effective to get her tested.