I need quick advice with elderly relative and health care professionals!

I apologise if this is long but I'm desperate and I know how good you ladies are.

I took over full time care of my 80yo grandmother last year and moved her in with me so I could care 24/7, she was doing brilliantly, we had a couple problems with her health (hospitalised with uti's and chest infection twice). Almost 8 weeks ago she began coughing up with signs of another chest infection, our gp came out and gave antibiotics which helped for a week but she continued to cough up (our gp has been off since she gave her meds due to family death or this would have been dealt with by now), a little over week later we had a nurse who gave stronger antibiotics that didn't work, another week and a nurse came out who rang a doctor that wanted chest x rays, I was told 3 days for results, 3 weeks later of me ringing everyday I finally got the results that said her chest was clear and they think it's in her upper airways (in those 3 weeks I had a lot of trouble with doctors, nurses, reception staff, having to take her for more testing including sputum, water, and bloods, doctors trying to take all her pain and blood pressure meds away 'to see if it helps', and my gma spent 3 weeks in bed weak) she picked up a bit and was able to move around again, a week ago she got much worse and has been in bed since, we've had a doctor out 3 days ago who said she wanted another sputum sample and took bloods, she said to wait another week and see what happens.

My urgent problem is she's developed marks on her lower legs and upper back 8 days ago, they look like extreme bruising with a red ring round but hasn't knocked or bruised the areas, she's continued to cough up a green/black mucus up for almost 8 weeks, she's very weak and has had 9 falls in 5 days (mainly at night), and 3 days ago she started hallucinating, we've had people standing over her bed laughing at her, someone pushed her out of bed, the whole casts of TV shows in her bedroom, she's confused 70% of the time and doesn't understand or remember simple instructions, times, or conversations, etc.

6 weeks ago she had her leg sprayed with nitro (I'm not sure the full name) for a possible type of skin cancer on it which also looks infected and is filled with a green puss, could this be the cause of her current health problems? I think she has an infection as every other time she's been like this that was the cause but the doctor won't do anything so what can I do? Any advice is appreciated, I'm worried about her and at my wits end.