I'm shooting .5cc of Sust EOD in my shoulders and glute with a 25g needle. The past 2 weeks I've just been shooting in my shoulders because its much easier and faster for me. The last 3 shots were super hard to get in....almost tough to go through. And when I pull the needle out, a trail of blood follows. Not much, just a small one. Am I hitting something? Why is it getting harder to go in? Thanks guys....I appreciate it!