When things are going wrong, people tend to take it to heart and think EVERYTHING is now on the decline... let's think about that.
The Stockmarket, looking at a daily timeline, will show great fluctuation. Expand to the whole year, assuming your stock is good, you'll see a much smoother upwards trend; just like life!
Don't be disheartened by off-days or stumbles as they are so insignificant in the who timeline of your life. Each bad day has a reason for being bad; perhaps it was external factors or an individual, maybe it was mistakes you made, or you didn't hit your targets. Every reason is a lesson in itself which you should reflect on.
Whilst reflecting, get comfortable taking full accountability. Someone else did something? It's your fault for reacting the way you did - it's a hard, but beneficial practise to engrain in you.
Bad days are common, they happen, but you can prevent them by learning from mistakes and constantly trying to improve.