What meditation ultimately does is to re-sensitize you to your emotions.

You'll find that as you meditate regularly, it will actually become more and more painful to hold onto beliefs and ideas that you were previously comfortable with - it's a by-product of having a fixed emotional range as humans do. And this pain can manifest in mood swings, irritability, even outbursts of anger.

This is a good thing!

Those previous (now painful) beliefs and ideas were not serving you but without viewing them from the perspective of your inner self (which is what meditation is doing for you), it is all too easy to get used to those uncomfortable feelings and make them habitual.

It then becomes puzzling how uncomfortable manifestations result when there is apparently nothing uncomfortable in your life...the truth being that, in fact, there is, but you are just not noticing it anymore.

Ever tried to sleep or work when it was noisy outside? Perhaps some builders were drilling or hammering. After a while, you find that you can actually ignore the noise and eventually not even notice it at all. And it's not until it stops that you feel the relief of the silence. The noise was actually taking a toll on you (perhaps making you irritable) but it was not until it stopped that you noticed how much better you now feel...as indicated by the feeling of relief.

Meditation does a similar thing. While you are in the meditative state, you experience the feeling of relief of letting go of thoughts, beliefs and ideas that were previously generating noise in your life.

So regular meditation is an excellent idea because it gives you a benchmark to judge how much you are in alignment with yourself.

But meditation by itself does not clear up those, now obviously painful, beliefs and ideas...it just highlights you have them.

But the awareness that you have them now gives you the opportunity to clear them up using processes like, for example, The Focus Blocks Method. Once you do that, your angry/upset moods will vanish.