Hi
@TimberYardBen, I well recall my very first injection on my own, 35 years ago and it took me half an hour to get round to actually doing it. Unlike you, the time it took thereafter gradually decreased, largely because I kept telling myself how well I was doing to manage it at all, and how much better I was starting to feel getting my T1 under control.
Everything I know and have been told by HCPs and on this forum says you're using needles way too long, particularly if you're slim, which it seems you are from what you say. Forgive me if this is teaching you to suck eggs but this may help:
https://www.diabetes.co.uk/insulin/how-to-inject-insulin.html 4ml needles are the standard as I understand it, because you're aiming to inject subcutaneously; longer needles if you're slim may well mean you're injecting into muscle which in my experience is a lot more painful.
My husband was truly needle phobic, which meant that in 30 years he never saw me inject. He overcame his phobia through necessity when he developed a condition which meant a lot of needles (true, not self-injecting) or else he'd die. I wish you the best in finding your way through this, because in the end, you only have two choices here.