B-12 shot needles?!

B-12 shot needles?

I am having to take B-12 shots at home and my doctor says the needles must be one inch long to go in to the muscle. The problem is that lately the shots really hurt and when I push down on my upper arm I can feel the bone and it doesn't feel like it is one inch deep to me, so I am wondering if the needle might be hitting the bone and if so is it doing me any good (fatigue is terrible lately). I wonder if I could change to a shorter needle?

I work in a doctors office and give people B12 shots weekly. Most of the time I use a 21 gauge 1 1/2 in needle and give it to people in the backside. Obviously you can't do this, so the next best place (like the previous poster said) is in the thigh. A 23 gauge 1 in needle should suffice, but I would avoid using the 1cc syringe. Use a 3cc syringe. Try and alternate the injection area and switch thighs. Please Verify with your Doctor that this is ok. I can't think of a reason it wouldn't be, but then again I'm not your Doctor and don't know your medical history.