Was Scarlett in a kind of shock after her marriage to Charles Hamilton that would extend past the birth of Wade?
I think that Scarlett experiences some distinct emotions after her marriage to Charles Hamilton. Shock is not one of them. The experience of shock would indicate a level of emotional commitment. For her to have shock would mean to have been emotionally invested to a significant degree. I don't think that Scarlett had anything related to emotional investment in Charles. Scarlett's only motivation in marrying Charles was to try to stir jealousy in Ashley. It failed and she became emotionally disengaged.
Her emotions after her marriage ended with Charles' death still do not meet the standard of shock. She is more despair at being a widow at such a young age and the social conventions that come with it. Little is made about Scarlett's birth to Wade, reflecting a continuing lack of emotional investment in the marriage. This would indicate that she was not in a state of shock. It seems more likely that she was more frustrated that her plans to ensnare the man of her dreams, Ashley, had not come to fruition. For this reason, I don't see Scarlett in a state of shock in terms of her relationship and marriage to Charles.