when is it too late to take a pregnancy test?

Okay so I'd like to take a pregnancy test for peace of mind. I'm 6 months PP and I've been experiencing ghost kicks and they're freaking me out. If it were that alone I wouldn't want to waste money on a test but a few months ago I had to switch birth controls since my IUD perforated my uterus and long story short still no period and I've been having funky symptoms but I've been blaming the birth control. It probably is the birth control and it probably is just phantom kicks and I'm probably NOT pregnant at all buuuut I don't want to be one of those chicks that had no clue lol that being said I know there comes a point where there's too much hormones and they test will say neg or your body stops producing HCG I don't remember which. But either way when is it too late??