Need answers to why we argue so much. Is this a major issue or something

that can be worked out? Alright guys..so we've been together for a year now. At the beginning everything was perfect we were so in love and happy and everything was great. Since I've started my second year in college, I don't know if it's just the school and work stress or what, but we have been getting into arguments quite often. I feel like our love life is completely non existent. We used to be very passionate..like all day everyday..and again, since this school year we don't ever have sex anymore. And it's not him, it's me. For some reason I'm just not into it. Idk if it's my birth control messing with my hormones or because I'm so stressed out all the time but I really feel like it's kind of affecting our relationship. I really love him a lot and we are so similar, like really we are the same person. So I feel like maybe that is why we argue so much? I don't know..We are both very stubborn and competitive. But when we aren't arguing we are so happy and affectionate towards each other. I just need answers