Zosia Mamet, Lena Dunham and Allison Williams
01/14/2013 AT 08:00 PM EST
You go, Girls
After winning two Golden Globes
on Sunday, Lena Dunham beamed while attending HBO's Golden Globe party at Circa 55 Restaurant in Beverly Hills.
creator – who wore an eggplant-colored Zac Posen gown
during the awards – seemed "too excited" to make it through the line of waiting reporters, an onlooker tells PEOPLE.
But after finishing up an on-camera interview, "Lena saw friends waiting for her on the sidelines and rushed over to them with squeals and hugs," the source adds.
Dunham's friends weren't the only ones waiting to celebrate with their pal, Lincoln
star Sally Field couldn't wait to congratulate her either! After Field – who is a big fan of Dunham's series – congratulated the young actress on her win, Dunham appeared starstruck.
"It's so amazing to meet you! Thank you so much!" she replied.
's Julie Bowen also stopped to chat with Dunham before entering the party.
But once inside, Dunham held court at a corner table joined by boyfriend, Fun guitarist Jack Antonoff
and costar Allison Williams, while Judd Apatow
(sans wife Leslie Mann
) sat at a nearby table.
"Lena and Jack seemed very a much couple. He was holding her hand in his lap as she chatted with the stream of people making their way over to the table," the source adds. "At one point, they took turns taking bites of a fudge pop dessert."
– Gabrielle Olya