I've had this happen to me before. The first time that I had a substantial amount of blood come after injecting, it dripped all over the floor, it looked like a crime-scene, and I panicked. Chances are likely that you nicked a vein, or your could have punctured all the way through it. You should be fine. All you can do, is hold a cotton ball over it until it stops and slap a bandaid on it. When you inject, just make sure that you aspirate before you push down the plunger - if blood gets sucked up into the needle don't inject. You don't want to pump T into a vein. As far as loosing T goes, you probably did loose some, as it didn't have time to absorb into the bloodstream. But it happens, nothing to worry about.