Still sick 3 months later: pneumonia lie flu, chest pain, painful & itchy rash, swollen lumps in armpits & mouth

3 months ago I got a very bad respiratory infection (with relentless coughing, mucus lungs & exhaustion). I had difficulty sleeping, breathing & had chest pain but I was travelling overseas so I couldn't see a doctor but took some viks & pain killers from a pharmacist. When I finished travelling (1 month later) my cough went away & I got two itchy red bumps (on my armpit & ingurinal area) that I thought might be bug bites. Over a couple of days they developed into a painful rash with blistered oval tops (kind of like many spots of ringworm) on both armpits, breasts, and the creases of my upper legs.

This rash became extremely itchy and painful. Nothing would cure it & I couldn't sleep or wear clothes. I tried prescription steroid creams of various strengths, antibiotic creams, prescription allergy pain, pain killers, and the full range of home remedies (compresses, aloe, oatmeal baths, etc.). The only thing that momentarily stopped the intense discomfort was calamine lotion, but that didn't work long.

The rash & itching got worse after a few weeks and I grew several large lumps in my armpits (about five in each with a large one the size of a big cherry). I also became very fatigued and weak feeling. With chest pain, numbness, and an inability to get up/move for a few days.

I've seen three doctors five times through this: one family doctor, emergency room, and a dermatologist. The first two told me they didn't know what was wrong, & the last said I had Pityriasis rosea (which I suspected I might have too).

In the last week, the rash, the pain, & the lumps have gone down. But the itching is still incurable & I have little red lines across my skin where the rash was (like the veins in an eye or bruise).

I've definitely still not been feeling healthy (I'm 25F, usually very healthy, no medications). & I can tell something is still wrong because I woke up today with a sudden swollen lump all along one cheek in my mouth up to my lips. It looks the same colour as the skin inside my mouth, it is a firm mass about 2cm long, causing numbness & pain in my teeth.

This has been a really confusing experience for me and I am getting more & more worried about what's going on. I live in a place with doctors who notoriously don't want to take things too seriously and I don't know where else to go to get some answers. Any advice would be very helpful!