If you inject needle in ur body will it kill u cuz i heard if theres air u die

It seems possible but unlikely. Read this... http://en.wikipedia.org/wiki/Air_embolism

You should make sure your doctor instructs you in the correct injection technique.

I'm no expert, but if I understand correctly the reason a doctor will hold a syringe upright, tap the side a bit and then squirt a small amount out is to bring any air bubbles to the top and then release them

But that's old school common syringes, most modern syringes used by diabetics are pre-dailed stick and click types for a specific dosage to eliminate mistakes, just have to change out the needle tip for each injection

I am about to begin injection hormone therapy and at my next Endo appointment.

I am to bring my filled prescriptions including my syringes (these are indeed syringes, not the "blast pens" diabetics use, which they need because of the frequency of their injections; they are dialed in and pre-loaded). At the next appointment, the Doctor will teach me how to self administer. Your medical professional should help you with this.

I did ask about the air bubbles and such and he said this should never be a problem, thereby, discuss EVERYTHING with your medical professionals.

I have understood that air isn't that much of a problem when you inject into muscle (intramuscular). It becomes an issue if you inject straight into a vein and accidentally get an air bubble in there.

I'm nowhere near a medical professional, this is just what I've heard.