If you think you may have dyslexia, you may find checklists published by the British Dyslexia Assocation helpful 

Dyslexia checklists - British Dyslexia Association (bdadyslexia.org.uk)

Developmental Coordination Disorder (DCD) or Dyspraxia can often overlap with dyslexia. If you think you may have signs of dyspraxia / DCD this website can give you more information: Dyspraxia at a glance – Dyspraxia Foundation

Dyscalculia - If you are concerned about specific difficulties with maths, a useful checklist can be found here: The dyscalculia checklist — Steve Chinn

Details on the Disabled Student's Allowance can be found here: Help if you're a student with a learning difficulty, health problem or disability: Disabled Students' Allowance - GOV.UK (www.gov.uk)