Praise be to Allaah.
Firstly:
The secret habit is an abhorrent and haraam action on the
part of both males and females. We have discussed the ruling on that and how
to deal with it in the answers to questions no.
329 and
101539.
Secondly:
What you have done of praying against yourself and asking
that you not be helped to succeed in obtaining high grades is something that
was not appropriate, because it was praying for something bad for oneself.
Falling behind in your studies is not a good thing; rather it would lead to
serious negative consequences. The Prophet (blessings and peace of Allah be
upon him) forbade the Muslim to pray against himself. It was narrated that
Umm Salamah said: The Messenger of Allah (blessings and peace of Allah be
upon him) said: “Do not pray against yourselves except for good things, for
the angels says ameen to whatever you say.”
Narrated by Muslim, 920
Muslim also narrated (3014) from Jaabir (may Allah be pleased
with him) that the Prophet (blessings and peace of Allah be upon him) said:
“Do not pray against yourselves, do not pray against your children, and do
not pray against your wealth, lest that coincide with an hour when Allah is
asked for something and He responds to you.”
Thirdly:
If a person swears to do an act of disobedience then he does
it, what he is required to do is offer expiation for the oath he swore. This
expiation is not expiation for the sin he committed; rather it is expiation
for the oath that he swore. As for the sin, what he has to do is repent
sincerely from it. Part of his repentance is regretting what he did in the
past and resolving not to do it again.
See the answer to question no.
103424
Thus, if a person swears against himself with the aim of
encouraging himself to do something or preventing himself from doing
something, as appears to be the case in your question, then it comes under
the ruling on oaths, and if he broke it then he must offer expiation for
it.
Shaykh Khaalid al-Mushayqih (may Allah preserve him) was
asked:
What is the ruling on one who says, “Insha Allah I should die
if I do such and such?” or he said “May such and such befall me if I do this
thing?” when he knows that he wants to go back to it and he said that in a
moment of anger? Is this regarded as being the same as an oath? May Allah
reward you with good.
He replied:
Firstly, it is forbidden for a person to pray against
himself…
Secondly, if a person prayed against himself in this manner,
intending to encourage himself to do something or prevent himself from doing
something, or to confirm something or to say that something was a lie, then
the oath was broken, then he must offer expiation for breaking an oath
(kafaarat yameen). For example, if he said, “If I do not go, may I fall ill
or die,” then he did not go. In that case he has to offer expiation for
breaking an oath.
End quote from Fataawa ash-Shaykh, 2/145.
And Allah knows best.