Teddi Mellencamp is getting candid about the alarming oversight in her cancer journeyand the lesson she learned about taking charge of her own health.The "Real Housewives of Beverly Hills" star, 44, opened up about how doctors missed a crucial step in her melanoma monitoring process, despite her regular visits."When you go to a doctor, you just assume thats it. Im doing what Im supposed to do," Mellencamp told Glamour. "At first, I didnt even really do the research on melanoma because I didnt want to know all of the bad things."TEDDI MELLENCAMP SHARES CANCER TREATMENT THAT WORKED FOR HER IN BATTLE WITH DEADLY DISEASEThe television personality has been vocal about her stage 4 metastatic melanoma diagnosis and multiple subsequent treatments, using her platform to raise awareness about the deadly skin cancer.Mellencamp shared how doctors may have overlooked the symptoms prior to her stage 4 diagnosis.WATCH: KYLE RICHARDS CALLS TEDDI MELLENCAMP INCREDIBLY STRONG DURING CANCER BATTLE"Theres a difference between self-diagnosing yourself and being an advocate for your own health," she told the outlet. "I never really thought about it because I was like, I go to a doctor every three months. Why wouldnt they get me checked?"LIKE WHAT YOURE READING? CLICK HERE FOR MORE ENTERTAINMENT NEWSAccording to Mellencamp, her highest-stage melanoma was a stage one lesion in her shoulder.Since her previous diagnoses hadnt exceeded stage one, doctors allegedly made the call to forgo full-body scanssomething Mellencamp now believes was a major misstep as they didn't catch her melanoma spreading.JOHN MELLENCAMP'S DAUGHTERS SLAM HIS FAMOUS EX"When I finally followed up on it, they were like, We didnt do the scans, because you didnt have anything above a stage one on your body," she recalled. "But look what happened."Mellencamp urged others to take a more proactive role in their healthcare.CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER"Its really being an advocate for yourself and your health if youre not feeling good," she said.The reality star continues to undergo treatment and has kept her fans updated via social media, where she shares not only her medical journey, but also the emotional toll its taken.Mellencamp was diagnosed with stage 4 cancer earlier this year after her melanoma metastasized in her brain and lungs. She underwent surgery to remove several masses and has been receiving immunotherapy and radiation.