I've never taken any injectable medications, but I hate needles, so I can imagine! It can sometimes help to have a partner administer the injection for you (I'm much better around needles if I don't have to look!). Alternatively, try to do some deep breathing and relaxation exercises to bring down your stress levels. If you really can't bring yourself to do it, have a chat with your doctor about systemic/oral medications that don't require a needle (or see if you can opt for a medication that is only administered once every few months).