One further thing....whilst not really advice as an aide memoire...
try and think back to the very first time you ever sat in a light aircraft. Try and think to the mixture of terror/awe/excitement/fun that you felt as you're instructor got you airborne. Try and remember that you probably thought "I'll never be able to do this". Try to remember how it felt to step up to a twin or complex..
ALL of these things are/were challenges, that seemed mountainous the first time, they were presented to you/us all. But, you work at it, you practice, you get better bit by bit by bit and now? You probably wouldn't think twice about going and flying the SEP you did your basic training in.
The IR is a challenge. It's possibly the steepest of the lot. BUT. Thousands of people before you have gone through it and successfully completed it. You'll be fine....Just remember Mountains are there to be scaled...and when you do, the sense of accomplishment is huge!