Aye an illness that has you floored enough to be in bed needs a bit of respect and time. No biggy in the context of the whole winter
I think it was the shorts.. -4°, get yourself some tights
Better to over do it and find your limits in November rather than March or July - as long as you learn from it.
Learn from it and it will have been useful. That and make sure you have, and use, good quality appropriate kit. Lecture over :-)
And don't go back to work when you still feel bad
I did that once and ended up very ill for a month.
Afterwards my boss told me not to be so stupid next time and always take as much time as needed.