Its very personal as to how long you need it before eating and it can change throughout the day, for instance I use Fiasp and need to take it a good 15-20 mins before breakfast, but for lunch and dinner I don't take til a min or two before eating. This does not mean you should use those times it means it'll be a bit of trial and error for you as you may need to take at completely different times
4 mins seems to be an odd number to pick
.
I tend to just carry my pen and needles in bag pockets or jacket pockets (I have many pockets
), and for hypos I use haribo sweets - cheap and they dont crumble or get destroyed when in pockets with various other things