Welcome to the forum, Tnshirley. We're glad you decided to join us.
There can be a lot of swelling in your leg following a TKR...especially when you try to go back to normal activities as soon as you did. Was there some overriding reason why you had to return to full time work? Most people at your stage are still at home resting, icing, taking pain meds and working with a therapist to gain ROM (range of motion). You would be much more likely to have less pain and swelling if you did that. Is it possible to take some more time?
I have some questions......what pain and anti-inflammation meds are you taking? How much are you working each day? Is there a commute too on top of actual hours on the job? What is your ROM and did you work with a therapist at all? Are you now?
"Normal" is a relative term with knee replacements. Everyone heals differently. There are a few on the forum who were able to go back to relatively normal activity levels at 6 weeks (not really at 4, though). Most cannot until about the 12 week time frame. And even then, it is advisable to work part days at first. You will be tired. This is major surgery and it really takes a toll on your body!
Sorry to ask so many questions, but it helps to have more details about your personal situation.