How do you keep your tranquility?

I do manage to keep my self calm at times. But lately i feel i can't control the bubbling anger within me. I keep lashing out over small things. Sometimes even the smallest things can annoy me. I have tried breathing techniques and i must say that they are very useful in keeping self in check but it makes me very restless or like being sap out of energy. If anyone can give me advice i be grateful for it.