Yes there are strict time limits.
Legal proceedings for medical negligence must normally be brought within three years of the date from which you first knew, or could reasonably have expected to know, that you suffered an injury as a result of medical treatment. For injury to children, court proceedings must be commenced before the child reaches 21. There are special rules if the claim involves a mentally incapacitated “patient” who is incapable of managing their own affairs.
It is critically important that you seek legal advice as early as possible as there is a considerable amount of investigatory work to be done before bringing a formal claim. The government are currently proposing changes in October 2016 which may affect your ability to make a claim and reduce any compensation you may be entitled to, so it’s best to act well before October 2016.