heidigold460.jpgCassi Thomas/Retna

Heidi Montag is hoping to prove she's still a celebrity by making an appearance at Hard Rock Hotel & Casino in Las Vegas to celebrate her 25th birthday.

The reality star, along with her hubby Spencer Pratt, partied at 35 Steaks + Martinis. We're told the birthday girl ordered Colorado lamb and lobster tail. Sounds delish.

A source from inside the club says partygoers celebrated her big day with a round of "Heidi fun shots" and, of course, champagne.

After dinner, Heidi and her crew headed to Vanity Nightclub where we're told the drinks continued flowing. The former Hills star also received a red velvet cake in the shape of presents.

Judging by her expression, we can tell it was a good night!