Can one appeal a signed parenting plan mediation agreement?

I signed off thinking that it was going to be the best for the kids but within one day I found out based on her actions it was a mistake. Is there anything one can do or is it to late. I though she had changed and was going to start being a mother again but now see it was nothing more then a ploy to get the child support.Can one appeal a signed parenting plan mediation agreement?
you are still going to pay c/s !

pimple