Feeling lousy and unhappy lately? You're not the only one and here's why ...

Have you been feeling a down lately? A bit sad? A little low on energy? 

Turns out, it's not just all in your head and you're not alone - there are many others feeling the same way due to Seasonal Affective Disorder.

A few years back, a Melbourne-based Facebook user asked the question surrounding why we don't feel quite right at this time of year. It went viral after many others claimed they feel the same.

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It turns out, we're probably trying to hibernate.

Duval reminds people that "it suddenly got a lot darker and colder recently". Some people's bodies may not have adjusted to the new season as quickly as they could have.

Her post shed some light on SAD (Seasonal Affective Disorder) and resonated with many people who commented and shared the status update.

Seasonal affective disorder (SAD) is a type of depression that's related to changes in seasons — SAD begins and ends at about the same times every year. If you're like most people with SAD, your symptoms start in the fall and continue into the winter months, sapping your energy and making you feel moody. Less often, SAD causes depression in the spring or early summer.

"Look at getting some vitamin D back in your system," Duval advises.

Her tips also include checking that you have appropriate bedding for the cooler temperatures (but also breathable bedding so your body does not overheat), drinking lots of water and staying in touch with friends during this "hibernation" period.

"You're allowed to go into screensaver mode sometimes," Duval wrote for those needing a reminder to slow down and take better care of themselves. "Plenty of creatures on this planet gear down over winter, and many mammals just go to bed permanently for a whole season, or go halfway around the globe to get the hell away from the cold."

Basically, DO NOT WORRY. You're not alone! Winter just scientifically sucks ... 

Where to get help:

• Lifeline: 0800 543 354 (available 24/7)
• Need To Talk: text 1737 or call 0800 1737 1737
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• Samaritans0800 726 666
• If it is an emergency and you feel like you or someone else is at risk, call 111.