Stories like this are one of thr reasons I wrote this post a few years ago :
http://www.scubaboard.com/forums/ne...ering-diving/283566-who-responsible-what.html
It is also the reason I wrote my book. This is a safe sport if one stays within the confines of their training and experience. And if it is done with full information and effective communication. Both of the last seem to be missing here. Running a new diver low on air is not teaching, task loading, or giving them a good lesson. IMO it is criminally irresponsible. Whether you actually got hurt is irrelevent. The fact is you could have been. That is negligent. I wouyld never dive with that instructor again and would make a conscious effort to let people know what he did. Yes you are responsible for your own dive and dive plan but new divers usually are not told this in stark terms. It is danced around and sugar coated so that you don't get scared and rethink the whole idea of getting certified. That comes from a training model based on profit rather than skills and education.
You now have an idea of just how deficient your training was. You may have gotten the skills, but the knowledge and a base to make good judgment calls was left in the trash. Time to start going beyond the text book you used and away from the instructor you used. Find new resources of information, a new instructor, and perhaps new agency. Disregrd the marketing hype of fun, sun, and quick easy rewards. It's bull crap big time. Time to become a diver as opposed to an underwater tourist. That requires study, dedication, and experience with buddies who will not put your safety anf life at risk to teach you a lesson. It requires real work and the ability to pick out quality instruction and training courses as well as a quality instructor. I have a whole chapter on how to do that as well. I will post an excerpt later. At work now and don't have access to the file.