I had protected sex but am worried I've contracted HIV

HIV is contracted by contact with body fluids. If you were using a condom the whole time that you had penetrative sex, and it did not break or come off, infection is unlikely. The best place to go for help is a specialist clinic called a GUM (Genito-Urinary Medicine) clinic, where they can give you information and advice, and testing if they feel it is needed. If you're in the UK you can search for GUM Clinics on the NHS website .