Late period

Kathryn

My period is 4 days late, but it usually varies by a couple or a few days (give or take), from month to month. My last period started on June 17, and ended June 22. Since my last period, I saw a dietitian in hopes of finding a healthy weight loss solution for myself, and about 3 weeks ago (from today) I changed my diet dramatically (mostly eliminating sugar from my diet). When would be an accurate time to take a pregnancy test? I’m getting worried.