For Almost Two Months Now I Have Been Applying, On

For almost two months now I have been applying, on my GP's recommendation) daily Efudix cream to (non-cancerous) lesions on my arms and on my bald scalp (I am 72 and I am in a fit healthy physical condition).
The spots I have covered with cream have over this time developed scabs and these scabs seem to be taking a very very long time to fall off (as scabs normally do). This morning, because a largish scab on my lower arm had hardened and looked particularly nasty I thought it might just roll off. It did come off easily enough but the skin underneath has not healed and I'm worried that I have done the wrong thing. Your thoughts would be appreciated. Thank you.