Why was I so worried? Do I need professional help?!

..One can be a little concerned which is quite normal, if their concern is validated, but to worry over something or someone before ones actually knows anything, is something one has absolutely no control over and is needless and futile, to say nothing of causing an ulcer in time..No, I do not think you need professional help right now just because you may worry..This is something you can ultimately gain self control of, if you think about it in "terms of reality & common sense"..Worry implies we can or do have control, where in fact we have, absolutely none..Filling the mind with other positive, reality/true thoughts, will in time heal these type of needless worry thoughts..Be concerned only once you know for sure or have proof that something may be very wrong..Remember also this is always about ones self..We always have choices...Take care...."Worry is as useless as a handle on a snowball"...

You are obsessing over her. I don't know the relationship between you two, but if she is your ex, you should calm down and not be so nervous or worried about her. It's quite common to obsessive over people, as a teenager (I'm only a year older than you), but it's not healthy. Get your mind of off her, and on to other things. Try to slow down your communication. Don't give, and learn not to expect, instant replies.
Instead of professional help, you could just google key phrases. Your problem hasn't reached severe levels to label you as dysfunctional.