You may just need a nap. Being tired seems to have a big affect on me. When I am tired I get frustrated and angry easier, and I cry a LOT. Problems seem big, and unsolvable. However, if I can just manage to sleep, a lot of times those "problems" disappear. They were caused more by my exhaustion than by reality. So, if everyone is seeming unreasonable, and unhelpful, and is generally "making" you mad, you might just try a nap. It usually works for me.