I find that when I am frustrated and/or depressed, the best way to relieve myself of those feelings, is to find out exactly what is causing those feelings.
You don't become frustrated or sad for no reason, there is always a specific event or events that have caused it, even though they may seem unknown.
Take an hour to yourself to lie on your bed and sort through your feelings and the time leading up to those feelings and narrow down exactly what made you start feeling that way. Once you know what caused it and why, then you now have control over it.