She stoned the jamaraat before the meridian out of ignorance and following others
Question

                I am a young woman from a Shi’i family but I follow the madhhab of Ahl al-Sunnah wa’l-Jamaa’ah in secret. I did Hajj last year with a Shi’i group and I was forced to stone the jamaraat on the eleventh and twelfth before the meridian, in accordance with their madhhab, and I did not know that they were going against the Sunnah in that. Do I have to offer any fidyah? Do I have to slaughter (the sheep) inside the Haram and distribute its meat to the poor of the Haram? How can I do that without my family finding out? Similarly, with regard to staying overnight in Mina, because of the overcrowding we reached it on the night of the twelfth at one a.m. Is that sufficient?.
Praise be to Allah.Firstly: 
We ask 
    Allaah to keep you steadfast in adhering to the truth and to guide your 
    family. 
The Sunnah 
    is to stone the jamaraat on the days of al-Tashreeq after the meridian, as 
    was done by the Prophet  (peace and blessings of Allaah be upon him) and 
    his companions (may Allaah be pleased with them). This is the view of the 
    majority of scholars. 
Since you 
    did the stoning before the meridian but you did not know that this was 
    wrong, we hope that there will not be any sin on you for that. 
If you want 
    to be on the safe side, if you are able to, then slaughter a sheep in Makkah 
    and distribute its meat to the poor of the Haram.  You can do that without 
    your family knowing about it, by appointing someone to slaughter the sheep 
    on your behalf in Makkah. 
Thirdly: 
The fact 
    that you delayed entering Mina on the night of the twelfth until 1 a.m. 
    because of the overcrowding does not require you to do anything either, 
    because you are excused in this case. 
Shaykh Ibn 
    ‘Uthaymeen (may Allaah have mercy on him) said: Whoever comes down from 
    Mina, for example, to do tawaaf al-ifaadah at the beginning of the night, 
    then is unable to go back until after dawn because of the crowding, there is 
    no sin on him. End quote from Fataawa al-Shaykh Ibn ‘Uthaymeen (23/240) 
We ask Allaah to guide you aright. 
And Allaah knows best.