I think the most import thing I have learned in life is, "You can't change the past". It's done, over finished kaput! So don't agonize, stress or beat yourself up over. Yiou can laern from it, you have control over your future. Start fresh RIGHT NOW. If you had carmel roll for breakfast, so what. Have a healthy on plan lunch and dinner and keep moving forward.
Persistance over perfection!
Failing to plan...is planning to fail.