Not sure what's going on

Have you tested yourself when this happens? I suggest you take your meter to work with you and as soon as it happens, test. You could either be very low or very high, and you really need to know. You can't do anything to treat this until you know which it is, or indeed if it isn't your BS at all. It does sound like a low to me.

Absolutely agree with The Bluetit.

And whatever your meter reveals, you can tackle with adjusting your lunch, or snacking before your weirdness hits.

By the way, what is your memory of the experience?

I would agree your best bet is to try and test to find out what your BS is at. However, if you are like me and feel that you don't want to test at work (I work in an office attached to a factory, no where is particularly clean) then try following the same eating pattern on a weekend and see if it has a similar effect that way you can test in the safety of your own home.

The other thing you might have to consider is the possibility of a false hypo. It looks like your sugar levels are normally running a bit high, so if you have recently started to try and reduce them you might find that your body is trying to tell you your are going hypo when you are actually just reaching a normal BS level, at which point you might be best just to try and sit it out unless you feel it is effecting your work too much.

You must be very careful here, I don't know if you drive or not but if you do it could be quite dangerous, because if you are having a hypo and you yourself are not noticing it but you are being told about it by someone else means you must not drive,