Family problems am I in the wrong here?

She will get over this. You just have to deal with the fact that she's going to still be your mother and want to mother you, regardless if you're a mother too. I argue with my mom over stupid stuff, kids stuff, financial stuff. It never lasts for long. Just tell her exactly how you feel and stand your ground. Sounds like you're doing just that. If she is still whining and complaining you can offer an apology but otherwise ignore her, she wants you to get bent out of shape over her controlling ways. That's how control freaks ARE.