You bet you deserve a GRUMPY DAY!!!!
Its so hard for non CP, family and friends to imagine what we deal with everyday! When someone makes that comment to me on my Grumpy Day, I thank them for noticing and let them know that sometimes its just too much to bear! Usually the reply is "oh I know, I'm sorry"! My thinking is NO YOU DON'T REALLY KNOW!
Hope everything is better today for you!!