yes you should call him. I don't want to burst your bubble but you can not talk about love at 17. You have crushes also you can not say that you love someone without being in a relationship first and really knowing that person. Any way you should call your new crush and tell him that u are a shy person and that time at the party u chickened out . U can make your "flaw" work for you in this way. If he rejects you.. but i don't think he will you should also tell Nick about you feelings cause as you can see u are not with him but because if you don't get him out of the way you ruin other relationships.Hope that I helped
What you really need to do is find some way to boost your own confidence. If you can't get past your shyness to even tell Nick who you have obviously been around a lot for a long time and should feel comfortable with, I don't see how you are going to get up the nerve to start up a relationship with what is basicly a total stranger. A couple dances at a party is nothing like spending all those years in the company of Nick.
Sheepdog is right, you should learn to evaluate your own feelings, sometimes you can't seem to get over Nick and then again,even when Nick is around you feel something special for someone whom you gave a second preference earlier. Probably your age has a lot to do with that, people mostly tend to remain confused when it comes to relationships,that can be of any age group. Now what I want to ask you is that whether you really want be with the guy you met later.Also give a thought about Nick and still if you feel connected,then don't wait to take an attempt in contacting him. Hope you make up your mind before its too late