According to my calculation, you're in the range of 5.7-5.9 inches. I'll take 5.8 inches as non-bone-pressed. You don't seem to be supine. Assuming an average NBP erect length of 5.07 inches and an SD of 1.15 inches, you would be roughly 74 percentile. If my estimated length is incorrect, tell me what it is and I'll revise the computations. Also, provide a BP erect length and I can calculate a percentile.
"What percentile and SD would start above average? And what would the criteria be for big, and huge?"
Anything above 50 percentile would be above average. "Big" and "huge" is arbitrary. To me, I look at 6.5 and think big and anything above 7 is huge. Anything above 8 is Goliath. Anything above 9 and you're pushing the limits of human anatomy. 10 is Godly.