it was scary for me at first. i wasn't even planning on sticking to it longer than six months, to be honest. the first days i kept telling myself '1 more day' then by 1 week, '1 more week.' before i knew it, it was two weeks, then six weeks, now she's 1 year and still going.
the first days ARE hard, though. it hurt so much! she cried a lot because my milk didn't come in until about the third day. my nipples were sore and cracked for the first week. i just kept applying lansinoh and within a few days, they seemed to heal and my nipples toughened up.
you can do it! stressing about it will just add more pressure and make it scarier.