Generally, you won’t know without consulting a lawyer who focuses on legal malpractice work. One of the key things to as is what was it the lawyer did that cost you something in your case, be it injunctive relief, money damages, or relief that you sought. An experienced legal malpractice lawyer is the only person who can answer those questions for you, review the prevailing law, and advice you on whether or not you have a substantive case that you should bring against that lawyer.