Thank you for your question.
Using a condom is definitely a great way to protect yourself from getting an STI; especially if it was used for both oral and vaginal sex.
If you are sexually active, it’s a really great idea to go and get tested regularly for STIs as most people who have an STI have no symptoms.
If you are writing from within Canada, testing for STIs is free of charge. Depending on where you go and get tested, you can use your real name, or a pseudonym (not real name).
This webpage (SmartSexResource) has a list of clinics that offer testing. It can be found here: https://smartsexresource.com/get-tested/clinic-finder
There is also this online testing service that may also work for you: Get Checked Online https://getcheckedonline.com/Pages/default.aspx It can sometimes offer that extra layer of anonymity for people.