5 mm is quite small, so I wouldn't imagine they are going into deep.........
do you rotate your sites sufficiently......?
it would be wise to actually find out your specific HbA1c number as you can then get a better picture as to whats really happening..........simply feeling OK inst enough to be honest, as damage could be happening but going unnoticed, and its all about minimizing that damage as the years go by....
my brother is like you in that hes on a mixed insulin and rarely tests, his HbA1c is about 8.5%, which isn't that much worse than my last and I am on a pump..........but 8% isn't that good, its not terribly bad, but likely will cause issues after many years.....
you may be around this mark.........
when do you normally eat and what?