Please ensure Javascript is enabled for purposes of website accessibility

Bad/good timing to leave?

I work at a small (<5) cpa firm, which is a tax-base firm. My main job duty is basically bookkeeping and do some tax individual tax returns plus all the admin job(asking phone calls, etc).While I don't mind doing the job that I am doing, I feel like there' no room to grow in this firm (this firm has been around for 10 years and the size is still the same). Also, my wage did not increase and it is quite low (minimun wage. period). I can understand this wage when I first started as I have no experience and the workload is not too much. But since I have taken over the job for the person who left, I was hoping to my wage will go up, but it does not.  So I have decided to move on. (cuz I really need $$ to support myself and family).  

I was able to get a job with much better paid at a bigger firm. I then told my boss one month in advance and she was furious, saying that I am selfish to leave before tax season (which I believe it will not start until two months later) and saying that my reputation will be ruined plus she will not give me good reference. Anyway, I have decided to leave. 

my question is: Am I doing something wrong? Should I leave at a better time? (cuz I heard that some recruiters do not like candidate who leave on Dec, but that was for audit though) Will my reputation be ruined just like what she said?

Please discuss/ advice. I really appreciate serious answer.