Britney Spears Rants About Mexico Trip, Claims Injured Foot Healed

Britney Spears says she's healing all on her own after a trip to Mexico -- which she says included cursing out strangers -- but visuals of her battered foot seem to tell a drastically different story.

Late Friday, the pop star posted a disturbing video of her horribly swollen right foot ... there's no way to tell how current the clip is, but in her caption, she claims she fixed it all on her own. As Brit says, "I was stubborn and did it my way !!! I didn't listen to a motherf***ing soul !!"

That doesn't seem like the wisest plan, based on the dark bruising around her heel, on top of the swelling. Remember, this is the injury she sustained during her notorious meltdown at the Chateau Marmont earlier this month.

Beyond her physical health, Brit ranted about a recent trek to Mexico where she swam naked in the ocean every night ... while drinking expensive wine, singing in the shower and shooting a dozen videos in new dresses.

That sounds great, but she also claims she screamed "f***" you" to someone's face, got pissed off during evening car rides because she wasn't driving and washed her own clothes in the bathtub.

The rant continues ... something about slathering her body in oil while wearing a swimsuit and filming it, catching a cold and then jetting back to Los Angeles.