Pregnant???

Mary
So my boyfriend of six months and I just broke up about two weeks ago but I have been on birthcontrol(nuvaring) our entire relationship and still am. We were having otherwise unprotected sex the whole time. Since I have been on nuvaring my periods have been very regular starting the day before my ring comes out and lasting six days. This month I spotted brown colored and only a little for the past four days but my period should have started today and hasnt yet. I have am not cramping but do have breast tenderness, am really tired and have a little backache. Should I take a pregnancy test? I know the chances are really low but I am freaking out a little since we broke up now would not be a good time and I don't have the resources to have a healthy pregnancy and raise a child alone.