We do recommend for the dear questioner that your desire for marriage which is the way of the Prophet Muhammad (peace and blessings be upon him). It was narrated that Ibn Mas`ud (may Allah be pleased with him) said, “The Prophet (peace and blessings be upon him) said: “O young men, whoever among you is able to marry, let him get married. Whoever is not able to, he must fast, for it will be a shield for him.” (Al-Bukhari and Muslim)
Turning to the question, we’d like to draw our attention to that whether your loan is a riba-based loan or not. If it includes riba, then it is obligatory on you to hasten to pay it off, even by the help of your parents. It is not valid that a Muslim occupies himself with fulfilling religious commandments before relinquishing sins. Moreover, if it so, surely the additional responsibilities for the new family will obstruct your fulfillment of the debt.
If there is no problem with that and with hope that marriage will not affect your study, you are urged to speak to your parents once more about your desire for marriage. Kindly and lovely, clarify to them your love to this girl and the expected benefit you will ripe of marriage. You can ask the friends of your parents to counsel with them about. Also, you may speak to the imam of a near mosque about this to speak to your parents in this concern.