I'd ring school and ask if they can organise an assessment for herJuggling. DD was assessed for dyslexia and dyscalculia earlier this year and will be getting extra time in maths as has got dyscalculia. There was no discussion of this at previous school and it wouldn't have happened had I not asked.
DS also now has extra time following dyslexia diagnosis last year, the SENCO was saying he will need to be 'done' again before GCSE as it only lasts a certain amount of time. We paid for his assessment, DD's was free through college, Someone else we know was diagnosed recently with dyslexia in year 12 after she approached her school.