I have a constant feeling of unease, I feel like something isn’t right even tough everything is. It’s very hard for me to describe this feeling since I don’t really know what it is myself, but I have it in the back of my mind for about a month now. This feeling doesn’t let me enjoy daily activities to the fullest and even while I’m happy I feel some sort of uneasiness. At first I thought it might have something to do with my mild anxiety problems but the feeling doesn’t actually make me nervous it just makes me feel like something is not right. Sometimes when I try to enjoy myself the feeling comes back and I start to feel like I’m just pretending to be happy. I feel like I can’t feel carefree anymore.
I don't claim to be an expert, I haven't experienced anxiety disorders first hand, but that feeling you described right there, is almost exactly how one of my friends phrased it "A constant feeling of uneasiness, worry and agitation." She suffered from General Anxiety disorder for a while and I remember particularly how frustrated she was about the fact that people kept asking her why, and having no clue where the feeling came from. And it sounds like you might have a similar experience.
You mentioned having mild anxiety, can you remember when it started? Did the feeling appear around the same time? Was there something that happened. It may be good to know the origin, but for a lot of people they don't know why and that's fine to. It doesn't mean you can't get better.
There are a lot of different things that could help ease it, my friend was very into meditating, which has an awesome healing ability I hear. Another important part is self talk, one of the major contributors to anxiety is all the negative thoughts running through your head, tackle it and turn it into something good.
I'm gonna leave you a link to a brilliant article I stumbled upon a while ago, whose done a lot of good about changing your inner talk:http://www.gateways-to-inner-peace.com/inner-talk.html