AceShowbiz -

Farrah Abraham has given herself a special gift on her 22nd birthday. Three days after the turning of age, the reality star turned porn star underwent a second boob job to replace her saline implants with silicone ones. Abraham, who legally could not get silicone implants until the age of 22, upped her cup size from a C to a D.

To In Touch which obtains pictures of Abraham on the operating room, the former "Teen Mom" star says she opted for the surgery because her saline C-cups "felt like water balloons." She now feels more confident with her look, claiming, "I look more natural. I want to look my best. And I'm looking amazing."

The second breast augmentation is her fourth plastic surgery in less than three years. Having spent a total of $30,000 to enhance her look, the mother of one doesn't plan to stop there. "There's definitely some pain, but that's expected," she admits, but adds, "What if I have a freak accident and I need something fixed, or if age gets to me, or I have more children and want a 'mommy makeover'?"

Though she's now known as a porn star with her adult film "Farrah Superstar: Backdoor Teen Mom", Abraham says she "would not get boob implants that were porn-star status." She explains, "I'm very realistic about keeping myself looking natural."

Gaining more attention with the porn video, Abraham has recently been in contact with big star Charlie Sheen. The MTV reality star texted the "Anger Management" actor first in May, hoping to score a role on his FX sitcom or if they could meet up. When she suggested that they could have a parent playdate with their kids or have some coffee together, he allegedly replied, "Coffee is for amateurs and grandma."

Abraham also let him know she would be in town that week and invited her to a birthday party of her friend, but Sheen wasn't able to attend. According to TMZ, the two are still in touch and are trying to work out a date.