When to test TTC cycle 1

🦉Sarah🦉 • 🍬27 💍2010 👦🏼1 👧🏼2 🐕2 🐹2 🦁Leo 🚸crossing guard

I know it probably gets asked a lot but should I test tomorrow? My last period was 9/15 and I should be 14DPO according to glow but if I say my period is late it says I’m 12DPO. I don’t understand yet. I just got the iud removed weeks ago and had a normal first cycle, I didn’t have periods while on iud but my periods are 30 days apart always start on the same day of each month.