I guess it depends upon whether you are nervous with reason (because you have a very small stash) or nervous without reason (your stash is big enough but nobody retires at your age, so you must have done your maths wrong, and your stash really must be too small no matter how many times you have done the maths).
I was nervous without reason. This is why I found MMM. I was sure I was wrong. But I wasn't - the maths was right.
And everyone lives on a different amount, so comparing your amount with anyone else's isn't really going to tell you anything. Living on your amount for several years before retirement is, as is living on your amount for several years after retirement. It is natural to tighten the belt a bit after retirement, because there are all sorts of spendipants things a lot of people seem to do as soon as they are retired - buy a beach house, a boat, an RV, go traveling... Things that they didn't do before retirement - maybe to replace work.
So, keeping a lid on expenses for the first year or so is probably a good practice. However, being afraid to spend a penny is just terrible! If you HAVE done your calculations correctly, just loosen up a bit. This is where keeping track of your weekly spending after retirement as against what you intended to spend, is probably quite important, so you don't go off the rails.