Those of you who have learned to drive, think back to your first driving lesson. You had to think of all that you had to do - look in mirror, hand brake off, foot on clutch, car into first gear. Now I'll bet you jump into the car and scoot off without a conscious thought. So worry not that these new skills seem a little strange, uncomfortable or daring. With a bit of practice and slight tweakings to suit your lifestyle and you will be confident without even thinking about it.
Setbacks do of course occur.
Analyse the situation with as much cool detachment as you can muster or chat it over with a friend and then reset your plans. Perhaps you had to deal with a difficult colleague who seemed to be agreeable till the end of the meeting when they stormed out. Your debriefing of yourself should focus on whether you had said anything to upset this colleague, whether they had other stresses to deal with in their lives and how you can next ask them what happened. Do not always believe you are to blame. Ask why and take it from there.