What Causes A Thick Pink Vaginal Discharge During Menstruation?

I had my period 3 days ago , usually when I get my period I bleed for 3days sometimes 4 but this time I only saw blood on the 1st day of my period and now I m having a thick pink vaginal discharge and with a little bit of itching but no burn. Last year I had a vaginal discharge for like 3days and then it went away and now I dont know whats wrong with me.