Welcome to HCM
We understand your concerns
I went through your statements. I suggest you not to worry too much. You are just about 15 and you started worrying about your sex organ. What will happen in future, if you go like this? I suggest you to think alternatively. Sex is not the only life.
The problem you are mentioning here about your private area are normal with every person. The ballooning while urination is normal. The "gone smaller" is just an illusion, because you are growing and your penis will not grow as fast as you. The burning sensation could be due to irritation or minor irritation. Keep the area clean.
You might need psychological counseling
., I am more than happy to provide telephone psychological counseling through healthcaremagic. Contact me through customer care, www.healthcaremagic.com.
hope this clears your doubts.
Available for further clarifications.