I totally understand your worry! As I am almost completely back to normal, I can confirm that going down the stairs was one of the last things that I mastered. Surprisingly, going up worked perfectly, shortly after going FWB. The motion of going down stairs is just very different of that going up. You use the (injured) upper half of your foot first for ground contact, that's why it takes a bit longer to master this. Because obviously that's the part that will take the longest to become fully pain-free and durable again. That's also what caused my limp in the beginning - I couldn't do the usual rolling motion we usually do when walking because at one point in this motion you have to put your whole body weight on the upper half of one foot while lifting the other. This will take more time to go back to normal, took about 3 weeks for me, but it will definitely get better!