I’ve been having difficulty breathing, chest pain, sore throat, I even noticed a lump on my butt, and the back of my neck that i hadn’t noticed before, my mom said my neck looked normal, and a doctor said my butt looked normal, just a little irritated and gave me ointment. I also had an inhaler and antibiotics for my lungs despite my oxygen level being 96% they said my lungs were kinda quiet and they saw post nasal drip. What could this possibly be?