OMG! NO! take it to a pro immediately!
is it white paint or has the pewter color come off? if its white paint, i think it could be repairable, especially if its waterbased. I got some paint (I'm a painter, it gets everywhere) on my lambskin 4-pocket and what got it off was a LOT of water and gentle rubbing with my fingertip. I tried kind of scratching it with my nail, but it made it kind of pull the top layer off, so i dont advise that! i really had to soak the area with water to get it out and it made the pocket that got paint on it slightly darker for about a week. its fine now, but i was freaking for awhile there, that happened about 2 months ago... its fine now though.
its gonna be ok! mega-hugs! i'm so sorry it happened to you, its SO distressing, i know!!!