Spotting before my period? Implation bleeding?

So my period isn't supposed to start for 4 days and it's always on time or a day late. I'm having some light bright red spotting and I've been having cramps the last 3 days nothing severe but little twinges of pain mostly at night time. Should I take a pregnancy test or is this normal for some of you. I usually never spot before my periods. And the only tome over ever had cramps before my period is when I had a chemical pregnancy back in march. Do you ladies think I should take a test? Or do you think it's just something weird with my hormones?

(Note: I am sexually active with my fiancee on a very regular basis, once to three times a day)