I, too, have looked back to see if there's any further advice I might offer.
I'm sorry to hear about your son, I hope he recovers soon. I will now repeat the old saw:
- What's the most dangerous place on the face of the planet?
- In between a mother and her baby.
So, you look after him. Fair enough.
Leaving that aside:
there are days when I am pushed way further than I am capable of, but I do it anyways and pay for it with 2 days of subsequent agony
External forces leave you
no alternatives? Really?
Yesterday, just by being a mom and a wife, I logged 3,700 steps and 12 flights of stairs without even trying. In the evenings, my knee hurts so bad and it gets even more swollen. I know I am over-doing it during the day, but I really have no choice.
Apart from your son, yes you do.
The Mantra is a distillation of the wisdom of BoneSmart. One line says:
- If you won't die if it's not done, don't do it;
And this is meant as only a slight exaggeration; rest really is best.
I set myself up for failure because my son (the injured one) asked me to take him to the AT&T store to get the new iPhone. Who can say no to someone who just had a near-death experience, right? Not me.
my husband had originally said he was going to drive me but when he heard I was taking my son to the AT&T store, he changed his mind (of course he did, he had a point to prove!)
You carry a firearm, correct? Ah, but you're 6,000 miles away

-- so, I can safely say that he was right, wasn't he?
TKR recovery is your time, for once, to be self indulgent. It's best for you
and it's best for those around you.
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As to your current horrible setback, as everyone has said you need to get it checked out. It won't be anything wrong with the knee itself, it will be a soft tissue problem of some sort. Good luck with it.