I so sorry for you you’ve got every right to feel sorry for your self,the kidney infection, very nasty but to lose your scheduled injections that is beyond a joke.
Having a fall under any conditions is nasty but to go down on your knees oh no I can imagine how you feel.
Warm water, bathing your hands and knees gently and some germolene or any soothing cream should help you feel a little bit better.
The I would suggest you let everything pass you by, curl up under your favourite blanket, perhaps watch the telly or listen to-the radio and a little doze this should help,
Never worry about feeling sorry for yourself, I do, I have times when I’m angry with the world and everybody in it and some people might say that’s pitiful, well it’s my life, my mood and I don’t care, so join me and we can feel sorry together.
Sending best wishes to you and do hope you feel better soon.