Janice Dickinson announced that she has been fighting breast cancer.

The reality TV star, who is often referred to as the world's first supermodel, spoke about her diagnosis in an exclusive interview with Daily Mail Online.

"Just two weeks ago, I was diagnosed with breast cancer - it's hard for me to say this," the 61-year-old said. "It's still quite shocking. Today I got very scared... I just get very scared and it hit me. But I am not gonna let that define me, the fear. I'm going to get through this, I'll be just fine kiddo."

Dickinson revealed that her journey first started March 8 when she had an appointment with her doctor about a small stomach problem. During her medical examination, her doctor recommended doing a full body test, which was when her doctor first noticed a "pea size" lump in Dickinson's right breast and ordered more tests.

Dickinson instantly knew something could be wrong.

"I'm always optimistic, initially when the doctor found the lump it hurt, it became quite painful when you touch it, that's the point when I knew this is serious," she said. "I went bingo, I have cancer."

The breast cancer diagnosis was confirmed four days later. Dickinson, who had a mammogram, received the terrifying call while she was out shopping with her 22-year-old daughter Savannah. The former "America's Next Top Model" judge said she was glad her daughter was with her at the time of the call even though she felt like a "nightmarish dream" was only just beginning.

"I got a call from [my fiancé] Rocky [Gerner] telling me the doctor was trying to get hold of me, [and] then the doctor called me and told me, yes it's positive for cancer," Dickinson said. "I was really glad Savi was with me at that moment because it was kind of an out of body experience. At that moment, I knew I had to be brave and I had to be strong. I had to find the courage I possess as a woman, that we all have as women, and then I had to put my chin up and my shoulders back and take it moment by moment."

The mother of two also recalled having to tell her son Nathan.

"I'm a lucky woman - I have two very talented and accomplished children, both in long-term relationships, who'd have thunk I could do this, but I have," she said. "My son said, 'I haven't cried in 20 years.' I was a proud woman to know I was so loved and so lucky and loved by everyone."

Dickinson has been diagnosed with ductal carcinoma in situ (DCIS), which is the most common form of non-invasive breast cancer. Although DCIS is not considered to be life-threatening, risk of being diagnosed with an invasive type later on can increase.

Dickinson, with the support of her family, is determined to beat the cancer and will not turn it into "a pity party." She has been receiving treatments and undergoing tests at UCLA in California.

She will be sharing her journey on the daytime series "The Doctors," beginning April 6.