Musnad Ahmad 28:479

Rawh narrated to us, Muhammad ibn Abi Hafsah narrated to us, Ibn Shihab narrated to us, from Isa ibn Talhah, from Abdullah ibn Amr ibn al-Aas, who said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, and a man came to him on the Day of Sacrifice while he was standing at the Jamrah and said: "O Messenger of Allah, I shaved before I threw [the pebbles]?" He said: "Throw, and there is no harm." Another came to him and said: "I slaughtered before I threw?" He said: "Throw, and there is no harm." Another came to him and said: "I performed the circumambulation of the visit (Ifadah) before I threw?" He said: "Throw, and there is no harm." He said: So I did not see him asked about anything on that day except that he said: "Do it, and there is no harm."