Is it too soon to test?

I typically have a 26 day cycle; the app is 98% accurate to the start day of my cycle. Once this year I had a 28 day cycle. I also suffer from awful cramps etc. My fiancé and I assumed due to more than a year of nothing happening, and some chronic health issues underlying that fertility would be difficult possibly. We aren’t “trying” but we aren’t not trying either. I am three days late on my cycle (tomorrow will be 4) and I do not have any tell tale classic signs of my period for my own body. I’ve had little aches but my cramps are debilitating for at least two days usually. I do have a very high stress job, but that’s never caused any issues before with my cycle. Is it too early to test/ should I wait a full week? What have some of your experiences been? I can’t lie I’m kind of antsy to see but I don’t want to get my hopes up.