First of all, stalking is such a strong word and is a bit much, but I would definitely call this obsessive and extremely pathetic of him. I've been in the exact same situation that you're in. The obsessive texting, nicknaming, continuous calling, constantly sending me stuff that I don't want, even sending me links to music videos on YT which he claimed were "tributes to me". It's all very uncomfortable, but I know that you've figured that out yet.
But, I'm going to help you out of this since nobody should be stuck like you are. And here's how:
1. YOU HAVE TO TELL HIM TO LEAVE YOU ALONE
This is extremely important, because boys -- especially ones as desperate as he is -- will take anything they can as a sign that there is a chance with you. For example, if you say "You're a nice guy, but I don't like you that way." then the boy will only hear the "You're a nice guy" part and run with it. He'll think that just because you called him nice that there is a chance for him to win you over eventually -- all because you said he was nice. Obviously, this isn't what you want. You want to be left alone, yeah? In order to do that, you have to be firm and cut to the point: "I don't like you. Stop texting me and leave me alone completely." This is crucial for you to be firm and not be 'nice' to him. Make it clear that you want to be left alone. If you don't, then he will continue pursuing you. Be firm, be clear, and be harsh if you have to. Niceness goes out the window if this guy is being as persistant as he is.
2. BLOCK THAT NUMBER, YO
It'll definitely give you some peace, and he doesn't necessarily have to know that you blocked him. You know, unless you tell him. Seriously, this will bring you some peace and stop the constant buzzing on your phone. I highly reccommend that you go ahead and take this action as soon as you possibly can.
3. IF HE CONTINUES TO BUG YOU AFTER DOING THE FIRST STEP, GET YOUR PARENTS INVOLVED
I'm being serious on this one. If he is still bugging you after you have clearly and firmly -- maybe even harshly -- told him to back off, then this is no longer an obsessive little crush: it becomes straight up harrassment, which is often in cases illegal, depending on where you live. your parents can most definitely help you to leave this guy alone, and they'll want to help you too. That's what your parents are there for, angel!
But I'm being serious. Do not worry about being nice. If he's being this obsessive, then there is no need to be nice to him since all he will do is use that niceness as false hope, which will only fuel the fire. BE FIRM. BE MEAN IF YOU HAVE TO. GET YOUR POINT ACROSS. BE HARSH.
By doing these steps, then he will surely leave you alone. And if he doesn't, grab your parents and get them involved. I followed steps one and two, and now he doesn't bother me. Sure, I had to be mean about it, and at the time I didn't like it, but in retrospect, if I hadn't then it might be even worse if I was nice to him.
I cannot emphasize to you enough how important it is to be firm and maybe even harsh if you have to. It's so crucial, I'm not even kidding. Just say "I don't like you, I don't want you texting me or calling me anymore. Stop it."
BE. FIRM.
Subject: Stalker Issues over Text? O__O (Help!) 
