You're a bit long in the tooth to be jumping ship. You'd be backed up behind all the bright young things already at the IB so your prospects would have been limited. Sounds from your comments on your work ethic, hours, and pay band like you're not too much of a mover and shaker in your current role. You probably did the right thing as it wouldn't have taken them too long to realize their mistake.
+++ As others above have said, asking for help and advice after you accidentally made the right decision rather underlines why you are where you are.
She's a bit precious isn't she...........