Hadith.2798 - Hammad ibn Uthman narrated from Habib ibn Muzahir, who said
I began the obligatory tawaf and completed one round when someone hit my nose, causing it to bleed. I left, washed it, and then returned to start the tawaf over. I mentioned this to Abu Abdullah (as).
Imam (as) said: "What you did was not correct. You should have continued from where you left off. However, there is no penalty upon you."