Big Lump After Teosyal Kiss Lip Injection

Around 3 months ago the doctor inserted what she called a "natural" and temporary collagen called "Teosyal Kiss" into my lips. Almost immediately after, I noticed a big ball of collagen swelling on my upper lip, which the doctor assured me would dissapear in a week.

Three months later, this huge ball has decreased in size, but is still clearly noticeable when I smile. The doctor just told me that my lips were "sensitive", that's why this huge ball appeared. I don't buy that, and I have really suffered with this horrifying result of my collagen lip injection. Is it really that my lips are sensitive, or did she inject the gel incorrectly into my lips? Please help me.