Fatigue is a normal part of PN for many people including me. It takes a lot more effort and exertion to do things that you used to be able to do more easily, such as walking. going up stairs, standing. working on something over shoulder level, getting in and out of car,etc. it just takes more effort with balance problems, getting tired easily, etc. Pain can also lead to fatigue.

If by perception of weakness you mean a feeling of heaviness in legs or arms when you are using them for a while, i get that. my legs become very heavy feeling walking upstairs, or for more than a short distance. my arms get heavy also when using them especially when i have to raise them to work on something overhead like changing a light bulb in a ceiling fan. My hands also cramp up if i use them too long.

Like you my actual strength is still good in my hands, feet, legs, and arms, even though my perception may not be that they are that strong still.