All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
Your ablution is valid and is not invalidated by the girl touching your shoulder with your sweater on. We have already issued Fataawa 85184 and 84131 clarifying that touching a woman does not invalidate one's ablution unless it is done with desire and if one touches her body directly without any clothing that separates them.
As regards repeating the Tashahhud in the same position, then this is not legislated, and the jurists stated that it is disliked to repeat the Faatihah (opening chapter of the Quran) and gave evidence that this was never reported from the Prophet or his companions . Likewise, the Tashahhud was not reported that they ever repeated it in the same sitting position, so it is disliked to do so; however, the prayer is correct.
Finally, we advise you not to open the door of whispering, as this is a widespread evil, and if one indulges in whispering, this spoils his mind and his acts of worship.
Allaah Knows best.