It seems like you are experiencing chronic (headaches present for more that 15 consecutive days in one month) tension headache.
The "severity" of a tension headache increases significantly with its frequency.
Depression, anxiety, tension are all triggers for this kind of headache (it is proved that people with chronic tension-type headache may also have imbalance in neurochemicals, like in case of depression).
Disturbed concentration, irritability, chronic fatigue, mild sensitivity to light or noise, difficulty falling asleep and staying asleep, are all features of chronic tension type.
Blurred vision is not so common symptom of tension headache, but, occasionally, this headache will be accompanied by nausea, blurred vision, and, hearing changes.