Shutdowns - how many is too many?

There's no "normal" really in either shut down or melt down. Some people never experience one or the other, some even experience both as rare. Others both very frequently and in different forms.

The key is, however yours are, is to work out what triggers them and try to minimise that.

Exactly, this is why I prefer to use the word normal only in relation to the self,  ie you know when you are experiencing something that isn't your own form of what is usual, otherwise as you say "normal" is such a problematic and misleading word.
I had to ask as I find strangers are almost never truly qualified to tell other people what is "too many" or "too few" or "normal" because we aren't in their position to know what their average benchmark history is to judge from.
I think it would be more helpful if Con could identify how they are feeling, like can they cope or are they feeling overwhelmed. Because I think that's the most important thing here.

Apologies if I've worded that incorrectly. My phrasing is mainly around myself not knowing if shutdowns are brought on by say facing more triggers/more overwhelm or if it's just something that will happen as I go about my day regardless of how easy or difficult a day is. So I didn't know myself if there is a "normal" and that shutdowns are something not regular and are usually brought on by the kind of day I've had, say.

Apologies if I've worded that incorrectly. My phrasing is mainly around myself not knowing if shutdowns are brought on by say facing more triggers/more overwhelm or if it's just something that will happen as I go about my day regardless of how easy or difficult a day is. So I didn't know myself if there is a "normal" and that shutdowns are something not regular and are usually brought on by the kind of day I've had, say.

I know it can be difficult to pinpoint our own feelings especially while we are still actively in them, but I would say it's important to trust your instinctual reaction because that is your emotional mind even if you might be second guessing it with the logical mind trying to analyse it afterwards. So if you are finding them unusual for you or they are bothering you or the frequency of them specifically is bothering you then yes it's fair to say maybe that is too much for you if it's making you feel that way. You're always the number one authority of yourself at the end of the day. I hope that helps, and not to worry too much about messy word use. Sometimes it's just better to get it out and express yourself even if it's messy than to not get it out at all, and you can always clarify points after the fact.

Shutdowns, melt downs and burnouts are all terms splattered around by us all in this place.  I'm not sure anyone has the definitive meaning.