Sounds like you're doing great, in practical terms. You have such a positive, amazing attitude and that's your best ally.
I think you can still gain more flexion. If you're concerned about your flexion, and your pain and swelling are minimal (or better yet, gone) you can do things to see if you can help it along. Do you bike? A stationary bike, at home or the gym, can be used to strengthen and work the joint. Outside biking, same thing. I'd recommend other advisors who know more about this, if you're interested.
Another option is to find an excellent physical therapist, one who understands rehabilitating TKRs, who can help with exercises you might do to improve your flexion. It might be a very gradual process.
Remember that your knee isn't finished healing yet. It still has some pain and swelling, so it's not done yet. So you don't want to force it or push it too hard. Stay active, enjoy life, and be a support player for Team Knee.