Late!!

Hey girls, im 2 days late, feel a bit nauseous and very tired. When would be a good time to test? Tested 3 days before period due date 2 days and 1 before too and all negative. Now im late but dont want to get my hopes up! Slight lower back pain so not sure if this is just a delayed period or early symptoms. Im never late though?so confused!! Dont want to get my hopes up if its nothing 😭 edit - also showing flu like symptoms today