The difference in the end of round and the beginning and end of bind off isn't going to make a noticeable difference in the look of the sweater. There's often a difference in the bind offs, decreases etc. but it is usually small fractions of an inch which do not affect the finished sweater.
The small hole at one end of the bind off should disappear as you knit further rows. There may be holes, depending on the decreases or bind offs for the neckline but often these are covered or closed up when you pick up sts for the neckband.
Check the directions and make sure that you're not supposed to decrease on the bind off or following rows. Is it possible that the shoulder decreases are finished or do they continue after the neck bind off?
Sounds like you're making great progress on your first sweater!