If you're doing it daily with no success then you probably need ovulation blood tests.
They're tricky to time with the GP, thats all.
But basically the GP takes bloods when you first get your period to get a baseline progesterone.
Then your progesterone has to increase otherwise you dont ovulate. So they take another set of bloods 7 days after ovulation to check its increased sufficiently.
If your cycle is irregular, for this second test you probably have to buy ovulation kits. You pee on this every night and it tells you when you are in the pre-ovulation surge. Ovulation happens (or is supposed to happen) 24 hrs later.
So when you get a positive result on the pee stick, you have to ring the GP and try to get an appointment within a week for 2nd bloods.
So the pee stick doesnt actually tell you if you have ovulated, it just gives an indication you should be within the next day.
But maybe you dont. Which is why you need the blood test.
If its over 30, then happy days. If its much less, then you havent ovulated at all and you need something like Clomid which mimics progesterone and will supply wht you're missing and hopefully you will ovulate then.