hi there it seems you have a short frenulum
or could be just that your foreskin needs stretching and excersise as your currently doing . but say in a few months time and you still cant full retract it
its the short frenulum issue.
there is a easy minor surgery they do which corrects the problem and it will be nice and slack and also will straighten it out its painless and you do not get put to sleep
its a normal annessthetic proccedure!
its pretty normal for it to be slightly on a angle when you pull it back on errection
nothing to worry about at all
craig