My little finger (90 degrees contracture) felt very similar to what you describe. Any pain (I had very little) gradually went away over the first month. The slight numbness feeling totally went away in the first year but it was never a problem. The finger is still perfect 12 years later.

My finger is perfectly straight and the same as before I had Dupuytren's. I did all of the therapy on my own. Mostly I was flexing throughout the day whenever I thought about it. It quickly became a habit. I never did anything painful in the flexing. I kept the scar tissue moist 24/7 with Aveeno lotion which I would massage the finger. Then after about three or four weeks I would wrap the fist with a self adhesive bandage cut at about 10" long and formed like a rubber band to slip over the fist for about 10 minutes. I would do that about four times a day.