So a couple weeks ago I got a refill on my syringes and normally the needle that comes attached to it is a 22G x 1 1/2 inch, but this time it was a 22G x 1 inch which I thought would penetrate my butt muscle but due to the needle being shorter I didn't feel it penetrate anything – I pulled back as usually to check for blood and luckily there was none, and then administered the shot regardless – Anyways, my question is: Did I waste my injection? Or is it no big deal?

It doesn't have the same effect as injecting into muscle but you'll be fine as long as a vein wasn't hit.

It takes longer to absorb but is about the same in the end. You didn't waste the shot.

People take their T subcutaneously (in the fat beneath the skin rather than in the muscle) all the time. You should be just fine.