Britney Spears Police Body Cam of Aftermath of Wild Flight From Mexico

Britney Spears walked away feeling just fine after her chaotic flight back to Los Angeles from Mexico ... even though a Customs officer says she was acting more erratically than usual.

TMZ has obtained body cam footage from the end of Ms. Spears' Wild Ride back in May, when sources told us she tried to light up a cigarette on a plane ... after it landed at LAX, an airport cop pulled up and talked to a U.S. Customs and Border Protection officer who met up with him at the plane's door.

It's hard to hear over the audio ... the Customs officer tells the newly arrived cop that Britney Spears was on the flight -- adding, "We get her all the time, today she obviously didn't take her meds. She's being very compliant; she's very nice, so to me right now, it's all good."

At that moment, Britney walks by on the tarmac, gives a little wave and strolls off ... looking great and not at all disheveled like previous pics we've seen of her.

The cop references an "outburst" that occurred on the plane ... an outburst we told you all about a few months ago.

Multiple sources told us Brit was hitting the bottle on the plane -- pretty normal aircraft fare -- before she tried to light up a cig onboard. We're told flight attendants told her to put it out ... which she did, though our sources say she was "difficult."

Once the plane landed, we're told Spears got a stern talking to from authorities ... though that must've happened before this agent arrived on the scene, 'cause she's not stopping for an interview or autograph here.

Photos taken of her from inside the plane showed a distraught and disheveled Britney -- sunscreen caking her arm -- in what looked like a verbal back-and-forth with one of the attendants.

Britney later said she didn't think she was doing anything wrong by trying to get her nicotine fix on the plane ... 'cause she says someone told her she could smoke, and she believed them. She also accused the flight attendants of not liking her from the flight's start.