Yes, they are all supposed to come with spare nibs. When they're worn out it does affect performance a great deal. Not sure where you are, I'm in the UK & they are relatively easy to find on the internet. If you do a quick search for Samsung note accessories I'm sure you'll find some. It might be a good idea to invest in a spare pen. I have one which is more like a conventional pen, and has an eraser on the top, really useful so you don't have to toggle the eraser when you want to get rid of something. I also have a Bluetooth S pen HMS1500 which you can connect your 3g tablet & phone to, you can then make and receive calls just like any other Bluetooth device (that's if you don't feel silly holding a pen to your ear & talking into it) I use this all the time - I can leave my phone or tablet on the desk & just have a pen in my pocket.
There are several YouTube videos on how to change the nibs - look out for it with the 10.1 if you can't find it for your model.
Good luck!
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