I legally don't have to let the cops in my house, right?

My mom went to the cops to come talk to me to tell me to calm down and everything because I've been off my meds for a while. And he said hes gonna come back Tuesday to check on everything. I'm willing to talk to him outside, but I'm not letting him in. He's not allowed to come in without my permission WITHOUT a warrant, right? And my mom wont' be here when hes coming, which is why I'm asking. I've seen so many cops abuse their power, and I just wanna know my rights.