Many conditions can cause throat pain including infections, inflammatory conditions and even tumors.
If throat pain is persisting for 2 weeks or more it should be evaluated. Of course throat pain might need to be evaluated sooner than at 2 weeks depending on the clinical scenario.
Infectious causes of throat pain include viral upper respiratory tract infections, bacterial infections (including Strep) and other less common infections. Inflammatory conditions including inflammation related to acid reflux or excessive use vocal use can cause throat pain.