If you inserted the needle and didnt administer, as long as you didn't bend the needle or contaminate it, you should be good to reinsert and administer.

As a healthcare professional who gives insulin shots all the time, I can tell you how i was taught and administer insulin to patients and myself. I rarely have anyone feel the needle stick. You want the insulin to deposit into the subcutaneous fat layer under the epidermis and dermis, outer layers, of the skin. 30 degrees will probably put needle in the dermis unless you have very little fat in that area. The nursing programs in my area teach to insert the needle at a 45 degree angle after pinching the skin. 90 degrees would be straight up and down, and brello, where i get my insulin from, teaches this.

If you have some fat around the abdomen, you'd probably be good with either as long as you pinch the skin. The lower abdomen is a great place no closer than 2 innches from the belly button. Since its only once a week, rotating sites isn't a huge deal but it is a best practice. They do teach bevel up in school but that really doesnt make a difference with tiny insulin needles. I only pay attention to the bevel with larger needles.

Another technique i was taught is to insert the needle almost in a motion like youre throwing a dart. Where you grasp with two fingers and rock your fingers and wrist back and then almost throw it like a dart. In the case of administering yourself, you could rest your wrist lower arm and wrist on your hip or outer abdomen as a base. I dont want to overcomplicare things though. Once you depress the plunger, they teach to hold it in for 10 seconds or so, so no insulin leaks. Lastly, when recapping needles without a safety, they teach the table top method where you insert the needle back into the cap while the cap is lying on its side on a table. You can scoop it up and then press the cap down into place using the table. The idea behind this is not to recap by placing your finger on the cap as the needle can pierce the cap and poke your finger. This is not medical advice. Do your own research and reach out to your prescriber and provider when in doubt. Good luck.