Late period

So I am not currently on birth control. I have been off of it for around 5-6 months. My periods even after stopping have been on time and regular and has never been late. I am currently on day 6 without my period. I tested this morning and it was negative. I am having occasional lower pelvic pressure/ pressure by my ovaries and some constipation. I have not had any nausea or spotting or cramping. Do I test again tomorrow or wait another week? Does this even sound like I’m possibly pregnant? I’m slightly panicking...