Jul.....I've just re-read your thread and I can truly understand why you are having problems with fatigue and pain. You returned to work sooner than you should have (at about 4 weeks out) and your schedule is putting a tremendous strain on you. Is there any way you can back off this schedule?
If not, then you must be realistic about your physical capabilities at this early point in your recovery. At 6 weeks out, you are in early recovery. We usually don't recommend that people try to go back to work until 10-12 weeks and then on a phased in schedule. Most people just can't handle work before that time.
In your case, you're pushing your body to do a full 12 hours by getting up at 5:30 a.m., getting ready for work, traveling there, walking to the job, doing your job, then walking back to transportation, riding 40 minutes home and arriving around 5:30 p.m. It's no wonder you are exhausted and in pain!
Please don't think you need to do any exercise on top of all this. You don't! What you do need to do is to find a way (if you must keep this work schedule) to incorporate some rest, icing and elevation into those 12 hours. Is it possible to take 2-3 breaks during the work day and get your knee up and iced? If you have access to a freezer at work, can you take some gel packs so you could ice on the 40 minutes to and from work?
If you must maintain this schedule, I suggest you immediately ice and elevate for an hour when you get home. Have hubby prepare your dinner, eat, and then then get to bed as early as you can. Use ice all through the night as you sleep and maybe take something like 1000mg of acetaminophen to help you relax and sleep.
When you are at work, do not sit for longer than an hour. If you cannot get up and walk around for 5 minutes out of every hour, at least stand and stretch for a few minutes at your desk. Try not to roll around on the chair too much as that gives your knee quite a workout. At least 3 times during the work day, do some gentle bends and stretches on with your knee just to the point of discomfort....not pain. This will help with your ROM. If you have access to stairs, put your operated knee up on a step comfortably and lean into it for the bends. For the stretches, put your operated leg up on a chair seat with the heel on te seat itself and straighten your leg. Hold that for a few minutes.
You must stop feeling guilty for not doing more. Constantly pushing yourself can actually cause you more problems than not doing "enough." Don't let anyone "guilt" you into thinking you aren't working hard enough at your recovery. At 6 weeks, your body is still healing! Most people don't begin to feel normal until at least 6 months out. And a full recovery takes a year or more.
Your surgeon did you a great disservice by suggesting you would be skipping and jumping right after surgery. What bunk! This is a major procedure and it takes time to recover. I'm going to post a couple of our recovery article links that I'd like you to read again so that you can appreciate what your body is going through.
The importance of managing pain after a TKR and the pain chart
Myth busting: no pain, no gain
Swollen and stiff knee: what causes it?
Activity progression for TKRs
Healing: how long does it take?
Chart representation of TKR recovery
Energy drain for TKRs
Elevation is the key
Ice to control pain and swelling
Please don't feel like I'm beating up on you....I am actually very, very concerned about the level of activity you are trying to endure at just 6 weeks out from your surgery. Your new knee is strong and you will not harm it. But....your extreme fatigue is a signal to me that the rest of your body is saying it's being pushed to the max. That is never a good idea.
Please post after you have read the links I've given you and let me know if there are any of my suggestions that you can incorporate into your recovery. Ideally, I'd love to hear that you could take a couple of weeks off from work and focus on getting yourself back on solid footing with lots and lots of rest. If that's not possible....let's see what can be done to help you feel better. We can work on a solution. I'm also going to tag our forum nurse,
@Josephine to see if she has any additional ideas for you.