Question for the experienced.

I just got married not too long ago. My period began the day before my wedding. Now it is exactly 40 days later and I have not yet had another period. I just started my <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period tracker</a> this week because of this so I'm not sure exactly how long my cycle lasts but it is usually around the same time of the month. Any advice as to when I should test? We are TTC.