If you test too soon, you will get a false positive from the trigger. Personally, I test on Sunday morning so that if it is negative, I have a day to collect myself before I have to go back to work Monday. Last IUI, I did that and started sobbing in church that day. I could not stop. However, breaking down in church is better than doing it in front of co-workers.
Sat or Sun morning should be fine. That will be 12 and 13 dpo, right? Better to know and have some time to celebrate or grieve.