Yes, it is possible to do a strep test at a pharmacy without a doctor's prescription. However, it is always best to consult a doctor if your symptoms persist for more than 7 days or worsen. In the meantime, you can try using Tylenol, nasal hygiene practices, and staying hydrated to help alleviate your sore throat. If you have a congested or runny nose, you may also want to consider using ibuprofen to help with pain relief, but make sure to check with your pharmacist first to ensure it is safe for you.