I say try doing different things. あなた might just be kind of bored with the things あなた do normally. Do something あなた don't normally do, または something that you've wanted to do but never got around to it. For example, 登録する a sports team または a book club または drive to the beach. I think that if あなた look around enough, you'll find something that あなた really enjoy to do.
Don't expect that you'll be happy all the time. Despite what most people believe, happiness (the emotion) is not what people want to strive for. The type of happiness あなた want is the sort of fullness in your moral behavior (like helping other people out and such, depending on your motives). So to be happy, あなた just need to start helping people out (with your motive wanting to help them out) and trying to make others happy (even if it doesn't results to happiness of that person, the thought is what counts). Just don't be selfish, share your joy with people, help yourself rid of bad behavior (of course, its not possible to get rid of it all, just do the best あなた can), etc. Of course, this is all ethics stuff. Happiness as an emotion is just to find the stuff あなた like and do that. Things that makes あなた unhappy and isn't necessary to complete, あなた get rid of. All of this has to be within the limits of legality and good moral behavior.