This is actually a very common problem, a great deal of people spend a day reading about chakras and decide that their going to open their third eye so they can gain some sort of psychic super-power. If any have succes at altering their chakra at all they have such little experience that they build up too much chakra in one area and neglect the rest.
For some, like you, this occurs naturaly or increases as a result of occult activity or aclivity of knowledge. Haveing an overabundance of chakra in an area is just as harmfull as having an underabundance, and all your chakras should be balanced.
Anyway, a way to fix this is as follows.
When you meditate, instead of focussing on expanding or loosening, try to cycle your energy, 'take' the excess and distribute it amoung the rest. Cleansing your other chakras first(as you have done) will open them and allow for more energy to accumulate, otherwise cycling will not help. By meditating frequently and focussing on all points of energy accumulation(not ignoring the third eye) the balance will restore itself.
Anyways, I hope this helped.