I’m disabled and have taken lots of painkillers over the years. I am also the self professed queen of headaches, though it sound like you might be able to steal my crown.
Most (possibly all) painkillers have their effects reduced with frequent use. I’ve been addicted to codeine. It started with one a day, which helped my joint pain quite a lot so I carried on. But then it didn’t work so well so I had to up it to two a day. Within a year I was up to 8 dihydrocodeine a day and it wasn’t doing anything for my joint pain. It then took months to wean myself back off the codeine.
You need to seek medical help with this. Though if you can’t get an appointment quickly, just start by dropping down to 4 tablets for one of your doses. Or maybe cut one in half and go with 4 1/2 tablets. It’s not going to be quick but it does work.
You really need to identify the causes of your headaches. I used to get so many but over the years I have learned what the triggers are. The list is long: too much sleep; not enough sleep; too much caffeine; not enough caffeine; bring lights; anything that can cause eye strain (reading, computer etc); going without food for too long, being out in the sunshine; sleeping badly (crooked neck). I can get away with alcohol sometimes, but sometimes not.
The two biggest culprits were the pill and artificial sweeteners (aspartame and acusulfame k, need to test sucralose but don’t want to risk a headache). In recent years I started getting a really bad migraine every month just before my period, building up to spending two days in a dark room throwing up. I’m now on amitryptaline and that’s dealt with those.
It’s taken me years to pin down the causes, I don’t get many headaches these days and not usually anywhere near as bad as I used to. If you’re organised (I never was) you could try keeping a diary to try to spot connections. And finally, get your eyes tested!