When should I test?? Or am I pregnant?

Hi all I haven’t been on here in a long time but my fiancé and I are trying, and I need advice to see if I calculated any of this correctly

My periods are somewhat irregular between 29-40 days. I started my last period on May 26th and had my ovulation between 6/9 and 6/15. We tried on 6/6, 6/9 and 6/17 and my supposed period is going to start 6/27.

I tested today and it’s negative…but the past 1.5 weeks I’ve been feeling extreme nausea (I’m never one to have unexplained nausea and I never vomit but have been on the verge), tenderness in my low abdomen and fatigue. I thought it was my PMS but realized it was too early to have PMS symptoms for me, I usually get them about 5 days before starting.

My cramps have been hurting a bit more today and has shot to my lower back. I noticed that I really want sleep more than normal (which is another one of my PMS symptoms but it’s been consistent for the past week)

Are my tests accurate? When should I properly test?