When is too early to test

anyone waiting to test I’m so impatient lol. I tested today nothing :( period starts in 4 days !!! I know I tested to early just thought I’d try. I know you should wait til your late but has anyone tested before and got positive? I know I tested two days prior before and got my positive but sadly ended in miscarriage so we are ttc again so I’m hoping this is our month :))