I concur with the sentiments of the earlier postings.
Importantly when you realised you had cocked up you did the right thing, we have ALL done it to a greater or lesser extent only some do not learn from their mistakes (some do not even realise or admit that it had happened.) One thing is for sure you are now a safer pilot and that is a GOOD thing.
The only people who do not make mistakes are those who do not do anything. You will make more mistakes but if you approach them with the same attitude you'll be fine.
I would estimate that on average I make at least one recognised "error" on every other flight - most are minor (frogetting to do a FREDA check, forgetting to switch tanks at the right time etc.) but some are real ring tighteners.
Don't wear a hairshirt and lash yourself - if you do not read PILOT magazine then have a look at the back page next time you get hold of a copy - ILAFFT - (I learnt about flying from that) is always excellent reading.