Pop Tarts

Scene & Herd: Where the stars were and what they were doing

A fresh 26-year-old Lady Gaga seen jamming out to Bruce Springsteen's Thunder Road, as she celebrated her birthday in a private-ride with friends at SoulCycle.

Ashley Tisdale poking fun at her Disney roots rocking mouse ears at Perez Hilton’s Mad Hatter-themed birthday party."Glee" star Amber Riley and Perez Hilton stopped and took  a group photo with the Backstreet Boys at the bash. 

Sean “Diddy” Combs exclaiming “Ciroc on Me...drinks for everybody!” to a room full of influential writers and bloggers at the SLS Hotel at a Ciroc event. 

Bruno Mars seen performing while Playboy Bunnies dance along on stage during the Playboy Mansions “Black & White” themed party. The party celebrated Bruno Mar’s April Playboy "Sex and Music" cover. Cameron Diaz was also at the bash, seen hanging with Coldplay’s Chris Martin, while they checked out the cover. Meanwhile, Britney Spears just chilled at the party spending time with her crew enjoying VIP bottle service.

Nikki Reed and Brenda Song spotted at Hyde lounge during the Lakers v Portland game to celebrate Superdry’s Santa Monica store opening.

Ben Flajnik and Courtney Robertson sipped cocktails at the SVEDKA Night of a Billion Reality Stars event. The newly engaged couple hung out in the "Jersey Shore" inspired “Smush Room” which had life-size cutouts of JWOWW and Vinny Guadagnino.

Songstresses Liza Minnelli and Fionna Apple performed in Atlantic City, New Jersey at the Borgata Hotel Casino & Spa.

Giuliana Rancic overheard congratulating Guns N'Roses Matt Sorum on his engagement at the Library Room in Hollywood for The LuxeYardStyle launch. Giuliana also caught up with TV hosts Jillian Barberie of "Good Day LA" and Debbie Matenopoulos from "The Insider."

Malin Akerman sported a cute mini dress as she hosted the launch of LACOSTE’s Spring/Summer women's collection at The Sunset Tower. Jenna Elfman, Former NFL player Michael Strahan and Jesse Metcalfe also took part in the festivities.

Joe Jonas spending time with friends at the Delano pool in Miami. The group of guys and a few girls chilled out in a private cabana, sun bathing, drinking (non-alcoholic) drinks and ordering food. 

“Vampire Diaries” Kat Graham taking the stage before a large crowd at The Hard Rock Hotels Present: The Sound of Your Stay Music Lounge during the SXSW Music Festival. Hip-Hop/Pop Star B.o.B seen chatting it up with Pete Wentz while backstage at the Lounge. The two had never met but had a lot to talk about when it came to their upcoming tour schedules.

Katy Perry escaped the rain after taking in the M83 concert at Coachella last night, and headed to Hennessy V.S. Presents DETAILS @ Midnight with pal and DJ, Skeet Skeet. The pop star, who has ditched her blue bob for sleek black locks - possibly due to influence from her preppy rumored boyfriend, French model Baptise Giabiconi - appears to be doing just fine since filing for divorce.

Danielle Jones-Wesley contributed to this report.

Hollie McKay has been a FoxNews.com staff reporter since 2007. She has reported extensively from the Middle East on the rise and fall of terrorist groups such as ISIS in Iraq. Follow her on twitter at @holliesmckay