Diddy's Wild Night -- Hangs with J.Lo!! But Gets His Maybach Scratched Up

Diddy had a huge night ... hitting up 2 L.A. hot spots where Jennifer Lopez also happened to be -- and there was a reunion -- but on the down side his Maybach got jacked up by an overzealous photog.

First, Diddy had dinner at Mr. Chow and that's where the pap gouged his sweet ride while trying to get a shot. Diddy noticed the massive scratch, and you have to see how he makes the pap sweat over the damage. Pretty funny.

Diddy left Chow just minutes after J.Lo ... and both ended up at Hooray Henry's nightclub. We're told both were at a birthday party for music video director Jessy Terrero -- and they did hug and chat for a bit inside. One source described it as "cordial" ... not romantic.

Still, they were careful to leave a few minutes apart -- and Diddy did recently call J.Lo's butt "a work of art." Sooo ...