Amanda Bynes -- I Just Got a Nose Job ... And I Already Want Another! -

Amanda Bynes followed through on her promise to get her nose fixed after seeing it in her mug shot ... and she tells TMZ she already wants to get another procedure ... ASAP.

In one of her post-arrest Twitter rants, Bynes said she was planning on "getting in shape and getting a nose job!"

Bynes -- who previously copped to having a nose job weeks before her arrest -- tells TMZ she got the procedure done yesterday in Manhattan and explains, "I have no bandage on. It's healing on it's own like my doctor asked."

But she's not stopping there, telling us, "I'm getting one more in 3 weeks, they are short amazing surgeries done while I'm awake but under general anesthesia. It's almost perfect."

She says once her nose "doesn't look so awful in photos" she will stop hiding from the paps.