Last night, Jay-Z did his first red carpet since the birth of his daughter, Blue Ivy. Jay-Z attended the “relaunch” of his 40/40 club in NYC, and he ended up celebrating with a mix of high and low celebrities like Alicia Keys, Ashanti, Spike Lee, one of the Mob Wives and… Warren Buffet…? Seriously, who organized this event? According to reports, Jay made an appearance at 11 p.m. and he hung out in the “security blocked” VIP section for most of the night. He left close to 2 am… and he was already pretty toasty by then, because he was doing shots of Patron all night. Is this the way new fathers behave?

Blue Ivy’s daddy is ready to party!

On Wednesday, Jay-Z was the man of the night at the grand re-opening of 40/40, his NYC club. In his first public appearance since wife Beyonce gave birth to daughter Blue Ivy on Jan. 7, the 42-year-old rapper (real name: Shawn Carter) was bum-rushed by reporters, photographers and well-wishers on the red carpet.

“Hi everybody!” the “Glory” rapper said amidst the melee. When the crowd congratulated him on Blue Ivy’s birth, he replied with a “thank you” and a huge smile. Still recuperating from delivering Blue at an “executive suite” at Lenox Hill Hospital, his wife of three years Beyonce, 30, skipped the night out.

Once inside the club, Jay-Z fielded a whole new crush of excited pals and fans wishing him well: Ashanti, Russell Simmons, Swizz Beatz, Selita Ebanks, even hard-partying billionaire Warren Buffett!

After parking himself by the upstairs bar, the rapper celebrated with shots of Patron and flutes of Ace of Spades champagne; throughout the night, he pulled out his phone and happily showed photos, presumably of his brand-new baby girl, to friends, who gave him and hugs and high-fives.

“Jay was beaming the whole time,” an observer says.

Also at the bash, the hip-hop mogul’s sister, Michelle, was overheard updating her own friends about her niece and sister-in-law. “Everyone is fine!”

No word yet on when Beyonce will make her first public appearance since becoming a mom.

After leaving 40/40 just past 1 a.m., the new dad continued the party at hotspot 1Oak in Manhattan’s Meatpacking district.

“He wasn’t doing anything crazy,” a source reports. “Just chilling, laughing, and talking.”

[From Us Weekly]

I get that Jay probably wanted to blow off some steam, and this appearance was partially about his business, not pleasure. But still! Blue Ivy is only a few weeks old (allegedly). Maybe Jay needed to get his drink on because of the controversy surrounding Blue Ivy, which has now become its own thing. Like, the mainstream media and legit news outlets are reporting stuff about “Beyonce’s controversial delivery.” I wonder when we’ll see baby photos? My guess is that they won’t sell the pics, right? But they might give the first photo away, in another month or so.

Photos courtesy of Fame & WENN.