should I test?

Yasmeen • Gave birth to my son 6.3.18 & now expecting my second bub due 18th of September ♥️
I am now 21 days late on my period, still no sign of it even coming. I'm meant to be due next week, just wondering if I should wait the week or 2, or get a test. I've had one test already last week, ended up being negative. I don't recall ever being this late, especially with having no sign or 'symptoms' of my period even making it's way anytime soon.