I've been vaping on and off for at least a year now. 2 weeks ago I started experiencing chest pain, a cough, wheezing, & tightness in my lungs for the first time ever. I started doing a nebulizer (and stopped vaping) and it was getting better so my doctor said to just continue doing that. Once it was better (but still there) I started to vape again but still did the nebulizer. Recently I felt 100% normal & started to vape but stopped using the nebulizer. Now I'm beginning to feel a tightness/flemmy feeling in the back of my throat but nothing else as of now at least. I don't think I'm allergic to PG or VG because I've used both for months on end and haven't experienced this before, Any idea what's going on? It kinda has me worried.