Local pharmacists can offer you free health advice. Many pharmacies operate extended hours on a rota basis.
https://www.nhs.uk/nhs-services/pharmacies/how-pharmacies-can-help/
https://www.nhs.uk/service-search/pharmacy/find-a-pharmacy
Over the Counter Medications
A GP, nurse or pharmacist will generally not give you a prescription for over-the-counter (OTC) medicines for a range of minor health conditions. This is because of government policy to reduce the amount of money the NHS spends on prescriptions for treating minor conditions that usually get better on their own. Instead, OTC medicines are available to buy in a pharmacy or supermarket.
https://www.nhs.uk/common-health-questions/medicines/why-cant-i-get-prescription-over-counter-medicine/