This might help those of us who are using short needles, very small amounts of insulin, and have real fuzzy kitties. I've found that sometimes even if I suspect I did a fur shot, I can't tell because the insulin is in such a minute amount, I can't find it by touching the area. So, since I'm using 8mm needles which help me avoid hitting muscle and are pretty short, and kitty is getting such a small dose of insulin, it's not always clear whether I might have given a fur shot. Often I'm not sure whether I'm in "kitty flesh" or kitty's ultra THICK fur, and came up with a possible check for this, other than finding a wet dot of insulin:
When you withdraw the needle, and you are not sure whether you got past the fur on kitty, try tipping the needle up against the shot point as you are withdrawing the syringe--that is, if you are in "kitty flesh" you will feel the needle "resist" against the last layer of skin. If you are in fur only, it will not have any resistance, and will just lift out through the fur, which would mean you probably gave a fur shot.
When you withdraw the needle, and you are not sure whether you got past the fur on kitty, try tipping the needle up against the shot point as you are withdrawing the syringe--that is, if you are in "kitty flesh" you will feel the needle "resist" against the last layer of skin. If you are in fur only, it will not have any resistance, and will just lift out through the fur, which would mean you probably gave a fur shot.