Question on glans sensitivity?

so i have just started to retract my foreskin and i noticed some white stuff and i know it is smegma and when ever i try to clean it in the shower with water i'm not able to because my glans are very sensitive and unusually they are more sensitive on the bottom then top so i try to suck it in and ignore the sensitivness but im not able to because it is to much to ignore so what should i do to stop the sensitivness and be able to clean that nasty smegma