I get the feeling and I’m only guessing: that maybe you feel like it wasn’t your best work. And to this I would say the work you produce is not a representation of you or reflection of you or what you’re capable of anymore than a piece of garbage is when you screw it up and throw it in the trash.
So while it’s easy for us all as creatives that have high standards to feel guilty about having work out there that we don’t feel is our best - in the interest of running a profitable business it’s important to sever the connection with what we have produced.
I think what you’ve done is great and if the clients are chuffed and what you’ve produced is fit for purpose, it’s a win.