Divorce sucks

My divorce lawyer was just awful. She gave me bad advice, did calculations wrong for child support, did not try to fight for me. I want to leave a bad review on Google with my phone number. Is that the worst idea ever? Not a terrible review but just "she isn't great, call me at xxxx for info".

Where does slander kick in? She was so awful, I just want to make people aware because she was expensive. I know I'll get blown up with numbers, but maybe not! To me, it's worth it to keep one person from trusting that awful lawyer.

Location: Louisiana