You should end binding off when you only have 1 stitch left...you need to knit the next to last stitch. For the very end, cut the working yarn leaving about 4-5in to weave in later and then just pull the yarn through the last hole. That's it!
As far as the tightness...a couple of ideas...sometimes it gets too tight when you are keeping the tension of your working yarn tight. Try to think of just letting the yarn flow through your fingers. The way you hold it and the amount of tension may very a bit with different yarns. Also, don't be tightening up the stitch after you bring the loop through. Just knit along and let it pull through on its own.
All of it is just practice...keep up the good work