Dreaming at your desk about your recent vacation? Having trouble concentrating? Feeling depressed and wishing you were anywhere but at work? You are not alone.
Doctors don't officially have a name for this. There's nothing specific in the official manual of mental disorders. But the Twitterverse calls your sadness #backtoworkblues or #holidayblues.
Feel familiar? This crankiness about the first day back to work is perfectly normal according to Dr. Angelos Halaris, a professor of psychiatry and behavioral neurosciences at Loyola University in Illinois.
"The stark contrast of the joy and freedom of family and friend time with the drudgery of answering a zillion work emails, can be hard on your emotional well-being," he said.
It's not just adults, either. A 2017 study found adolescent depression, anxiety and feelings about everyday hassles appeared to be tied to the end and beginning of school-vacation cycles. It might come as no surprise that teens felt less anxious and depressed during the vacation.
Halaris said it's not unusual for people to react badly to their return to work for the first couple of weeks.
"There is a real sense of loss that comes with this transition period that makes us all a little sad," Halaris said.
Even if your time off didn't meet your expectations, you still may not be happy about getting back to work and away from your family. It may be even tougher after the Christmas holiday.
"We see this in study after study. People tend to have high hopes coming into Christmas thinking time with their family will be like the Waltons or thinking Santa will bring us all that we want, but it never totally works out that way even if it was a really good holiday," said Dr. Randy Hillard, a professor of psychiatry at Michigan State University.
"That can leave you feeling let down, too. We see this every year with a lot more calls to the crisis line, a higher number of deaths and there are even studies that show the letters to Dear Abby sound much more depressed after the holiday."
Those feelings might be enhanced by our tendencies to overdo, well, just about everything, said Halaris.
"It's more than likely during the 10 to 14 days of the holiday season with Christmas and New Year's we tend to go overboard even in the best sense -- overeating, overdrinking and not sleeping enough -- that all sets the stage for the post-holiday crash."
Winter adds to this perfect storm of gloom. It still gets dark early. Much of the world is cold. It's wet. Seasonal Affective Disorder can be particularly acute if you enjoyed a sunny beach vacation over a winter holiday.
So what can you do to bring back that vacation feeling even if you're at the office?
"Treat all colleagues like they are insane for the next couple of weeks, it works with family members, too," Hillard said. Know that most people feel like they are in the same sinking boat.
Book another vacation -- even if it's a mini-vacation. Experts say having something to look forward to can ease the bite of the back to work blues.
Ease back into work. "Don't jump into the cold water, you'll have a heart attack. Ease your way back into your routine," Halaris said. Set small goals to feel a sense of accomplishment.
"If you ease into this with full awareness, rather than trying to plan a ton and hope to get it all done in the next 24 hours, it helps."
You can also try to add some variety into your worklife. If you're always stuck at your desk, set a timer and take a brisk walk or try to fit in a workout.
Don't dwell. Know that something you enjoyed has come to an end, but make peace with it and know it will come back again. Resist feeling sorry for yourself.
"Self talk and being optimistic is important," Halaris said. Look at kitten pictures online if you need a little lift.
Take advantage of the break in your routine and start new office habits. Even if it is something small like being friendlier to random co-workers or getting up to walk away from your desk once an hour, it helps.
Reflect. Think about what you liked about your break and bring an element of it to your work. Pajamas may not be in the dress for success plan, but if you enjoyed connecting with friends you don't normally see, squeeze them into your weekly schedule, even if it's for a 15-minute coffee.
And do connect. People who are blue tend toward withdrawal.
"Push yourself to interact even if you don't feel like it," Hillard said. Company helps avoid misery. "Prescribe yourself an evening out with relatives or friends in the upcoming weeks," Halaris said.
"Without, of course, being drunk or overeating or staying up too late to start the cycle over again. It can help you be mindful that while the holidays are over, yes, but you can have fun again soon."
CNN's Sandee LaMotte contributed to this story.