yes it is but you shouldn't worry about that right now
It is not massive, 6inch is the average size.
Better than average.
Well, there is no 'normal size'. 5.3 inches for a 13 year old, is a little on the smaller side, actually, but it should grow more throughout puberty. An average for a 13 year old would be 6 3/4 in.
If it so happens that it puncuter your rectum when going in, yes.
No, the average penis length is 5-6 inches.
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