She did not complete ‘umrah and she swore that she would not do it until she reached the age of forty
Praise be to Allah
One of the mistakes that some people make is not asking about something that happened until a long time has passed, which is indicative of heedlessness, because what they should do is hasten to ask so that they can make up for whatever can be made up.
Whoever enters ihram for either Hajj or ‘umrah must complete it, and it is not permissible for him to interrupt that ritual before completing it, because Allah, may He be exalted, says (interpretation of the meaning):
“And perform properly (i.e. all the ceremonies according to the ways of Prophet Muhammad (blessings and peace of Allah be upon him)), the Hajj and Umrah (i.e. the pilgrimage to Makkah) for Allah”
What you and your mother should have done during that time was perform ‘umrah, and you should not have obeyed your father by abandoning ‘umrah.
Based on that, what you must do now is go back to Makkah to complete ‘umrah by doing tawaaf and sa‘i, and cutting your hair. Thus you will exit ihram for ‘umrah.
You must also avoid the things that are prohibited whilst in ihram, such as wearing perfume, cutting your hair and nails, wearing gloves and niqab, entering into a marriage contract, or having intercourse and doing the things that lead to it.
If it so happens that you have done any of these prohibited things out of ignorance or because you forgot, then you do not have to do anything further.
As for the one who falls short in asking, or knows that he must do something but does not enquire as to what exactly it is, or he knows that he made a mistake by failing to complete ‘umrah and that he was obliged to complete it but did not do that, then he must pay a penalty for each of the things that are prohibited in ihram that he committed, before he completes the ‘umrah that he started and exits ihram from it in the proper manner. For more information, please see the answer to question no. 104178.
If you got married during this period, then you must repeat the marriage contract with your husband; so your guardian must do a new marriage contract for you with your husband, in the presence of two witnesses, because you were in a state of ihram and that remains in effect until you do ‘umrah and complete it.
See the answer to question no. 176422
With regard to your saying “I swore that I would not do ‘umrah until I was forty years old” this does not include the ‘umrah that you did not complete, because that happened before you swore the oath.
But if you want to do ‘umrah again before you reach the age of forty, then in this case you must offer expiation for breaking an oath (kafaarat yameen), because the Prophet (blessings and peace of Allah be upon him) said: “Whoever swears an oath then sees that something else is better than it, let him do that and offer expiation for his oath.”
Narrated by Muslim (1650)
You should not let that oath prevent you from doing an act of obedience to Allah, and you should discipline yourself to refrain from doing such a thing in the future. It is not wise or sensible at all for a Muslim to let his anger make him do such things, for he may swear an oath or say something or do something out of anger, then regret it after that, when it is too late and it is not possible to make up for what he did.
And Allah knows best.