Tired

These feelings I have I don't quite understand. Is it fear or is it doubt? Am I just feeling down and out? I should be happy and I know that but I can't shake these feelings and I don't know why. I can't talk to anyone about it, everyone else has more important things going on in their lives and I don't like feeling like a burden and I don't like having nothing positive to say. I can put on this happy face and make it through most of these days but sometimes it is exhausting. The happy face is getting more and more painful anyway. I shouldn't be feeling the way I am and I know that but I don't know how to come out of it. Maybe I just need to work harder at getting over it...