Is it, "why do I feel so depressed?" or "Why do I feel so angry?" Mmmmm, this will cause your mind to go looking for rational reasons for why you feel this way... or for old memories of times when you have felt depressed or angry..... leading you to feel more depressed or angry.
If you want to change your mood, you will need to change your questions. You can try any of these, and within a minute you will have changed your mood.
"Why do I feel so happy?"
"why do I feel so peaceful?"
"Why do I feel so blessed?"
"Why do I feel like laughing?"
These questions will cause your mind to go looking for times when you have felt this way, and in so doing, lift your mood. Your mind will remind you of times when you have felt good, you will find yourself visualising these happier memories. It takes a little discipline, but if you can practice the technique below, you will find your mood lifting.
Technique: To use any one of these questions, allow yourself to find a comfortable place to relax. Next breathe slowly and deeply. To practice this style of breathing, breathe in to the count of three, and breathe out to the count of three. Have your eyes closed during this time. When you have practiced this breathing for around two minutes, then repeat one of the positive questions above slowly over and over... for 1 minute to change your mood.