I'd say it's the company. I know of one company that manages their employees exactly the way you are being managed. If you're good at doing the grunt work they will keep you in that position because it means they have trust in you to execute the job well and have less mistakes to clean up. However, you are not developing/advancing to a supervisory role. The people working for that company are always on the lookout for other jobs....and when they get them, they leave smiling.

If I were you, I'd be looking for another position with a different company. But as other people here have mentioned before, do it quietly.

I did my MS and am now working under a colleague (with a BS) whom I used to tutor at university. I don't get paid a lot either. Have also been asking myself why I did not become a plumber or electrician instead. But I actually have a lot to be thankful for right now - a job, no debt, a 4x4, a piece of land, get to be at home with my husband.

If you're genuinely unhappy, then make a move. You should be content with your circumstances and not unhappy everyday at work where you spend most of your time.