Dreams are extremely dependent on the context of the person. But I read this and I wanted to offer an idea of what it could mean.
It sounds to me that you might be stuck on this decision you had made in college to choose this degree, it may be disconnected to what you feel fulfilled by. Or even a choice that you had made in that stage of your life. Or there could be someone who doesn't see your life choices as amounting to much, like I said there are many factors that I have no idea about.
Do you frequently have feelings that you have wasted a large portion of your life? You said that your degree isn't entirely useless, that itself is an indication that you don't have that much faith in what you chose.