You need to talk to a lawyer in order to determine if you have a case.
Your lawyer is going to look at a lot of factors. It isn’t just whether or not there is negligence–and if there’s negligence then there certainly is a claim to be pursued–but whether or not it’s worthwhile pursuing is another matter.
It has to make sense in order for the lawyer to pursue it; it’s his time too, and it has to make sense, most importantly, for the client to pursue it. And, if it doesn’t make sense, then it’s up to the lawyer to explain to the client that it’s something that he or she may want to think twice about before pursuing.
Basically, what the attorney looks at, and what the client should think about, is not just whether or not there is negligence, but whether or not there are damages, and whether or not the damages are significant enough–and related to the negligent act–to make it worthwhile pursuing.