9 Days Late..Test?

Alright guys, I had what I'm pretty damn sure was implantation bleeding 6 to 10 DPO and now my period is, according to Glow, 9 days late. Should I just Test and get it over with? I'm so nervous 😩

Also, I have had some symptoms like cramping and nausea and lightheadedness, so I just want to ask, do symptoms kind of pile on top of each other and follow you everywhere at any time or is it usually just like an on and off thing? Bc so far they're on and off so it makes me question myself