@dawny,
Not sure where you are located -- but you cannot get unemployment if you quit.
However, it would seem that you should be covered for some compensation for being injured at work - you could contact your state's labor department. Being in a vet's office -- it is likely with such a small business they do not have insurance for this, however, some states may have a special trust fund for workers' injured working for a business that does not have workers' compensation insurance. You may be able to file a claim and/sue your employer.
I would contact labor department in your state any way - as it seems depending on the laws in your state -- you should have not been forced to go to work.