If you are talking about Bilko's calculator, it is based on the level 33 Callaway spin ball. Balls with more distance will fly farther.
If you are talking about Kat's wind calculator you have to Tweak the settings for head and tail winds to your ball.
With Kat's using my settings I came up with 158.5 yards.Which would be my 7 iron hit at around 96% power using -61% spin.
There are a couple of things that could have caused your shot to go 10 yards too far. The most obvious one is accidentally changing clubs and not noticing. That has happened to us all at one time or another.
The second thing which I am guilty of quite often is forgetting to add spin on the shot after doing my calculations. No added spin can definitely cause a shot to go 10 yards or more too far.