To eliminate pain form injecting, I found that I could tap around with the needle tip until I found a patch of skin that didn't feel it, and just go in there. Drawing back on the needle to see if there is blood is the thing to do. I didn't even bleed at all after an injection, except a couple of times where I went through a vein on the way down into the muscle, and did not realize it until the injection was over and I bled a little when I pulled the needle out. But the estrogen doen't get into the blood that way, so it's not a problem if that happens.