Spotting in instead of my period??

<a href="https://play.google.com/store/apps/details?id=com.glow.android">Glow app</a> said my period is supposed to start today but I started spotting on Friday and it’s become lighter today. Could this be from my fibroids? Should I wait a few days to see if my period starts before going to the dr? No pms either only the regular fibroid pain that I get before every cycle.