Based on your degrees, background, experience and current level of certification, I don't think more credentials will really do you that much good. Alas, my analysis leads me to suggest that you spend more time and effort looking for your next job and that you don't settle for making less than you're worth. That doesn't mean you should quit your current job to look for other employment, but you should probably plan to spend 6 months to a year researching and looking for your next position, and don't just "settle" for something else because it's marginally better than where you're at now. To some extent you're a victim of a tight job market, but I can't help but speculate that you may be selling yourself a little short of what you're actually worth.
Keep at it, look hard and long and don't settle for the next halfway decent thing to come along. Dig until you find a job you really want, then jump on it with both feet!
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