This depends on what’s available in your area for people your age.  Usually, you will be able to test for chlamydia and gonorrhoea, the two most common and often symptomless STIs. For these, you will either need to take a vaginal swab or provide a urine sample.  You may also be able to test for HIV and syphilis, both of which are tested for using a blood sample and possibly Hepatitis B and C. Brook offers STI home testing kits for chlamydia and gonorrhoea in some parts of the country and with Brook you can also test at home for HIV, Syphilis and Hepatitis B and C in some areas. Free STI test kits in your areaFind your nearest sexual health clinic