It's not even a month yet since you had this major surgery. It really is a bit soon to be reducing your pain medications. The time to do that is when you find you are forgetting a dose and not feeling increased pain.
Josephine suggested this way to handle coming off the pain medications:
"Here is a suggested schedule for cutting back on prescription pain medications. Stay at each level for 3-4 days or even longer if you notice the pain symptoms increasing. This schedule assumes you are starting with one pill every 4 hours before beginning the reduction process.
1 pill every 6 hours and 2 at bedtime
1 pill every 6 hours and 1½ at bedtime
½ pill every 4 hours and 1½ at bedtime
½ pill every 6 hours and 1½ at bedtime
½ pill every 8 hours and 1½ at bedtime
½ pill every 8 hours and 1 at bedtime
1 pill if you are really doing something active during the day and 1 at bedtime
It is usually better to wean off these meds over several weeks, not several days. But.....if you are still having pain, then your body is healing and you still need pain relief. And in this case, I would discuss your pain management with your GP instead of your surgeon."
It sounds as if you allowed yourself to be led into doing too much at PT last time. Remember this:
a. If it hurts, don't do it and don't allow anyone - especially a physical therapist - to do it to you
b. If your leg swells more or gets stiffer in the 24 hours after doing it, don't do it again.
Take a pain pill - you need it.
It may be that your own doctor (or your surgeon) will be willing to prescribe some Tramadol for you when the current pills run out - it's a useful "step-down drug that works well in combination with Tylenol.
I feel caught by the need to keep moving and the safety of pain control if I don’t move much. Surely I should be further on than this by now.
No, you shouldn't be further along by now. recovery from a knee replacement takes a long time - as long as a full year for complete recovery of all your tissues. You've had major surgery that caused a lot of trauma and it takes time to heal. Recovery is more like a marathon than a sprint.
It's easy to expect too much, too soon, but do try to allow your knee the time it needs to heal.
You only need to keep moving gently. Your knee doesn't need a lot of exercise.
It's not exercising that gets you your ROM - it's time. Time to recover, time for swelling and pain to settle, and time to heal. Your ROM is there right from the start, just waiting for all that to happen, so it can show itself.
There's no need to rush to get ROM (Range of Motion) because it can continue to improve for a year, or even much longer, after a knee replacement. There isn't any deadline you have to meet:
Myth busting: the "window of opportunity" in TKR
And don't start worrying about getting addicted to the drugs. It's unlikely to happen:
Myth busting: on getting addicted to pain meds