Hi.
It's perfectly normal to have crushes, but celebrity crushes are especially exciting and tend to last a bit longer because this person is an idealized figure. In other words, since you have no actual contact or one-on-one experiences with him, you can only imagine all the great things about him. You have no actual proof that he is as you imagine him.
Think about what happens when you meet a new guy in real life. You might find that you truly like him, that you are neutral or that he kind of turns you off. Since you don't have the luxury of having met Joe in real life, you cannot know whether or not you love him.
This is probably a phase. Your attachment to Joe Jonas will probably fade eventually--or at least become less consuming. However, you shouldn't spend so much time thinking about him that you are neglecting important things in your life like your studies, activities, family and friends. If your crush is affecting these areas of your life, you may need to make a conscious effort to integrate more activities in your life or focus on other things.
If you can't help yourself and you find you are obsessing over Joe and letting other things fall by the wayside, you may want to speak to a school counselor about your preoccupation. He or she can do short-term counseling or refer you to an appropriate mental health provider.
Take care.
