I feel like everything I do will ruin my septoplasty

The first thing to say is that if your surgical team say that all looks good then they will mean it. At five days post op the nose will swollen internally and there will be some remnants of the surgery in terms of blood and mucous. There may be some dissolving stitches. The very best thing that you can do at this stage is to heed the advice and leave it alone. Whilst not pleasant, anything that is troubling you at this stage will normally work it's way out of it's own accord. A Q-tip or finger can do harm.