Late Period

So my period was supposed to start on The 22nd which is 4 days ago (according to glow) my sister told me to get a pregnancy test so I bought a dollar one, we have only used the pull out method because my body doesn't react well to birth control and condoms don't agree with my lady parts! So my question is should I test? We were not trying as we have an 18 month old and a 6 month old! Every baby is a blessing and we would love it either way but financially we are not ready for another lol