United Kingdom, Aug. 9 -- Britney Spears has revealed that she was left with a droopy eyelid following a botched Botox procedure.

The 44-year-old singer urged her fans to "be careful" with cosmetic treatments as she demonstrated the unwanted after effects of the injections in an Instagram video.

Britney claims that the injector "put so much Botox in this left eye that it drooped down like that", as she showcased its impact by pressing her eyelid down with her finger.

The Oops!... I Did It Again hitmaker explained that, four weeks on from the procedure, her eyelid is "just now starting to raise up and be normal again".

She said: "It's so embarrassing it was like that."

Britney then implored her social media followers to "be careful if...