How do I know if I have just Balanitis or Thrush?

So I'm fourteen, and all of a sudden, I noticed my penis becoming itchy. A few more days, it got severely itchy and my balls also started getting itchy. I noticed the foreskin near the head of the penis has a crusty, dry texture and there are a few white cracks where the skin folds. The tip of my penis is also getting narrower i.e its harder to pull back foreskin. How can I tell if my disease is caused by bacteria, fungus, or its just irritation? Also, what over the counter medicine or cream can I get without needing a prescription?

sounds like thrush some balantitis is caused by it its basically just redness irritation itchyness and also skin cracking and peeling if u notice anything like that apply some clotrimazole cream for 3 days to a week u should see improvement

not being able to retract the skin on the penis fully is called phimosis doctors can give u a steroid cream to apply in severe cases circumcision is required

what i suggest u do is purchase the cream as fungal infections can cause phimosis and make it difficult to retract the foreskin back if u still have issues after 7 days i suggest u make an appointment to see a doctor /dermatologist