Am I pregnant please help!!!

Hey I'm struggling me and my boyfriend had unprotected sex 1 day before my period was supposed to start well it was late 3 days after we had sex I had milky white discharge during those 3 days and today I'm spotting clumps of blood and my back hurts me and my boyfriend are going to get plan B today but I don't know if it will work and I don't even know if I'm pregnant please comment and help me I'm thinking about just buying 2 test and take one today and one next week what do y'all think????