Is the feeling that God does not accept good deeds and charity due to obtaining a usurious loan correct, and what should be done in this case?

Borrowing with usury is among the gravest of forbidden acts. You must hasten to repent to Allah by returning the principal amount of the loan without the usurious increase, if possible. Otherwise, repentance involves desisting from the sin, regretting it, and resolving never to return to it. There is no harm in disposing of the borrowed money by giving charity or spending it on permissible things, for the prohibition relates to the borrower's liability, not to the money itself. Abandoning acts of obedience under the pretext that Allah will not accept them is a mistake and a ploy from Satan. The correct approach for one who has committed a sin is to repent and increase in acts of obedience, for "Indeed, good deeds do away with evil deeds," and "Follow up a bad deed with a good one, it will erase it." Beware of despairing and losing hope in Allah's mercy, for "Do not despair of the mercy of Allah. Indeed, Allah forgives all sins."