Sahih Al Bukhari (84)

حَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، قَالَ: حَدَّثَنَا وُهَيْبٌ، قَالَ: حَدَّثَنَا أَيُّوبُ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ أَنَّ النَّبِيَّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ سُئِلَ فِي حَجَّتِهِ فَقَالَ: ذَبَحْتُ قَبْلَ أَنْ أَرْمِيَ؟ فَأَوْمَأَ بِيَدِهِ، قَالَ: "وَلاَ حَرَجَ" قَالَ: حَلَقْتُ قَبْلَ أَنْ أَذْبَحَ؟ فَأَوْمَأَ بِيَدِهِ: "وَلاَ حَرَجَ".

Ibn `Abbas (may Allah be pleased with him) narrated that somebody said to the Prophet (peace be upon him) (during his last Hajj): "I did the slaughtering before doing the Ramy [throwing the pebbles]. The Prophet (peace be upon him) beckoned with his hand and said: 'There is no harm in that.' Then another person said: 'I got my head shaved before offering the sacrifice.' The Prophet (peace be upon him) beckoned with his hand saying: 'There is no harm in that.'"