Is loving each other at the age of 17 right or wrong?
Your question is too vague for me to give you a good answer. You have love for your parents from the time you are a small child, and that is certainly right.
People are quite capable of falling in love during their teenage years, but it doesn't imply that getting married at 17 would be a wise choice. In fact, in many areas of the world, a person is not able to marry until they are older. Even if marriage were possible, there is a problem that arises when a person is below the age of majority -- you can't get a good paying job, sign a contract on an apartment, and do many other legal transactions. Wisdom would be to wait until a marriage relationship is practical. And if you are both truly in love, then the delay will not matter. "Love is patient ... " (I Corinthians 13:4).
But the use of the word "loving" has been abused. To some people it doesn't mean a strong preference for another person, but sexual intercourse. Such is not proper when two people are not married. "Marriage is honorable among all, and the bed undefiled; but fornicators and adulterers God will judge" (Hebrews 13:4).