Well, it feels terrible when something happens like that.
That is the kind of thing that can lead you on a personal quest for answers to the situation that may take you all kinds of places, some not even necessarily connected directly, or not seeming to directly connect to, martial arts.
Ki, Qigong, Philosophy, Religion,Prayer, Meditation,Therapy Groups, New Age Movements,Stress Management Training, Weapons Training,talking with people who have combat experience from wars,are only a few of the avenues that, if one is honest, one might search.
Ultimately the fact is that no one is a Superman, that if you are taken aback, caught off-guard, sick, or just not feeling "with it", this can happen.
The training that one can do, as given in the Tohei book, can enable one to recover very quickly, however, and I hope everyone is able to get a copy of this wonderful manual of Ki training and concepts.
Of course, some people are overagressive and will attack the attacker, needlessly getting themselves and anyone with them into a could-have-been avoided conflict.
Mas Oyama of Kyokushinkai once said that the strongest ki a martial artist could have is just the starting point for a person with a strong religious faith.To hear a martial arts master say a thing like that gives one pause, indeed.
One does need to keep one's awareness about them at all times, if this is possible.Master Tohei says the key to ki is to keep one's focus on the "one point" throughout the day.
But he says it is enough to train in breathing fifteen minutes in the morning and fifteen minutes in the evening.This is interesting because my Okinawan Kenpo teacher said, when I asked him how he trained(he is formidable indeed), that he, too, spent about fifteen minutes in the morning.I asked him on what, and he answered, "Oh, you know-Basics."
Since I had been training with him twenty years, I was perhaps ashamed to ask him to elaborate further.:-)
Wish I had, now.But Mr.Tohei's advice, plus kata, will serve.