I think you should get another job first. Keep the old job while looking for a new job. Then consider further education. That's my oponion anyway
Rgds
Billo
I know someone in a similar situation who decided to do a postgrad (so only 1.5 years) and stayed in the same boring (but easy) job. I was amazed at how her attitude changed in the job for that year and a half. She was much happier knowing that she was eventually leaving. She was also happy not to have to deal with learning a new job, dealing with new colleagues etc. while trying to concentrate on study.