Take yourself off to hospital if you start to struggle with your breathing. I have had pneumonia before and it can make a sudden turn for the worse even on antibiotics, both times I have needed intravenous antibiotics to move it. The last time they did this by getting me to visit a hospital each day for 3 days and injecting them right into my blood stream. This really worked.
The first time I was in hospital for 10 days and on a range of antibiotics to kill it. Really nasty. We have such low immunity once one of those bugs get into our systems it is really hard to throw it off.
Please monitor yourself and if you feel you're going downhill go for help.
Thinking of you, it is exhausting but its really important you cough that phlegm up. I was given physio both times to help me.
Keep us posted, worried about you, golitho