Well recognised condition where regular long term use of pain killers eg paracetamol leads to chronic headaches. Tends to be dull, particularly in the morning. And you might still get your migraine on top!
Of course, might be difficult to differentiate from chronic daily migraine (defined as more than 15 days in a month) or other headache that is not well controlled! It appears the majority of those with chronic migraine do not take or are not offered appropriate preventive medication.
To exclude, always have a day free of analgesia (including triptans) after any day where it has been used, and use a maximum of 3 days per week [Dr Abu-Arafeh’s advice] or else maximum 10 days per month.