Salam Dear Laila,
Thank you for your question and for contacting Ask About Islam.
Concerning my opinion in such a sensitive matter as the concept of a “love affair” in Islam, I will refer you to one of my previous answers. It is a similar question, in which another teenager asked about Islam’s view of love.
Although the other question was about a different kind of love, yet the answer was a general one. In that answer, I directed the young man to the ethics of such a relationship, as stated in Quran and Sunnah. These ethics are to guide people regardless of their age.
To read that answer, please click: Love Affair: A Noble Sentiment or Fake Love?
On the other hand Laila, I don’t know if I can advise you to get married while you are both at this age. This is because I don’t know if you are mature enough to take such a responsibility!
I will also refer you to another answer about the right age for marriage, in order to give you some guidance in relation to such an important point. To read that answer, please click: What is the permissible age for a girl to marry?
In case you can’t get married right now, I recommend that your relationship should be in the light of and with the blessing of your families. The young man can propose to marry you so that you can get betrothed.
Under such circumstances, you might be able to see one another in quite a halal environment, among your families.
Again, in case your families do not accept such an early engagement, then there is no way that you can continue your secret relationship. In such case, you will just expose yourselves to God’s anger, despite your being very religious.
With the help of Allah and your strong iman (faith), you’ll overcome this difficulty of waiting till time is right for you to get married insha’Allah.
As for the second part of your question, about the “dirty thoughts” that you “keep to yourself”, Prophet Muhammad (peace be upon him) had a saying in relation to such context.
‘Righteousness is good morality and wrongdoing is that which wavers in your soul (heart) and which you dislike people finding out about’ (Sahih Muslim)
Such bad thoughts, only kept in your imagination, time by time they may incite or even excite you to interpret them into acts. Such a God-fearing girl like you should always try to keep herself clean from inside, as well as outside. While the thoughts aren’t haram, since thoughts pop into our minds and we can’t control that and sometime this is from the shaytan, you should seek refuge in Allah from them and from acting on them.
May Allah reward you for your piety.
Best of luck and I hope this answers your question.
Salam and please keep in touch.
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