"We all feel sad at times," Hartstein says, and noted that it's totally normal. But this does not mean that you are depressed. The big difference between someone who is clinically depressed and a person who is simply sad is that depression lingers for longer periods of time. If your sadness is primarily situational, then you are likely not depressed.

Hartstein tells Romper that it is absolutely normal for you to occasionally feel scattered, but this is not necessarily a sign of depression either. Maybe work is pulling you in a bunch of different directions or can't figure out where to move. Feeling scattered is normal when coming across tricky situations that will take some time (and possibly some serious soul searching) to resolve, but they don't necessarily mean you are suffering from depression.

Picture this: You woke up and had a nice breakfast with your partner, then got to work and immediately snapped at your coworker. By the time the end of the day rolls around, you probably have another six feelings creep up. It's like you're the queen of mood swings lately, and you can't help it. Although our culture associates mood swings with depression, Hartstein says they "do not fall into the category of a mental illness," .

Did you just have a fight with someone you love, followed by a bad day at work? Then you likely feel that you had a rough day and want to wallow in your feelings. This is a reaction to being sad, Hartstein says, but not necessarily a sign of depression. It's OK for an event to affect your overall mood for a couple of days. If it becomes weeks of wallowing, however, then you may need to speak with your doctor about further depression symptoms.

Not showering after a rough day isn't unheard of and is another reaction to being sad. The big difference between this and depression? According to Hartstein:

"The sad feelings may pass within a day or two. Someone with depression will have a harder time moving out of those feelings. They last for longer periods. Family and friends may vocalize concerns when those behaviors start to last for longer than a few days and up to two weeks."

Although someone with depression typically withdraws, someone without depression may temporarily withdraw or sequester themselves for a variety of other reasons, Farrenkopf says. This can be true after a particularly rough week at work or in your personal life, or even simply because you are an introvert and need some time alone. Withdrawing for short periods of time can be normal, and you likely shouldn't worry that you may have clinical depression unless it is a feeling that continues for longer than a couple of weeks.

A person who appears less socially responsive, shallow, or lacks follow-through might seem depressed, but it could also be related to memory or distractability issues, Farrenkopf tells Romper.

"A key would be to look for behavior patterns that are enduring versus temporary or new or surprising," Farrenkopf says.

Fatigue may be a common symptom of depression, but it can also derive from many other sources, Muskin tells Romper. For instance, those who are feeling physically ill may also experience fatigue as part of their overall symptoms of having the flu.

Being easily irritated at times can be more of a symptom of simply having a bad day, Muskin says. Who hasn't snapped at their partner after a coworker pissed you off? It's normal to feel irritated after high stress situations, and this temporary symptom is likely to pass quickly if you don't have clinical depression.

Feeling fatigued can often lead to losing an interest in some of your favorite activities, which is a telltale sign of depression, Muskin says. If, however, your waning is simply temporary, then you're likely not depressed. You might be exhausted from being sick, from a fight with your spouse, or from a big work presentation that has taken up even your free time at home — and this has led you to skip out on that cooking class or stop going to your weekly Zumba session. That's likely not depression, since your loss of interest is likely due to the temporary rough situation at home or work. Taking some time off can sometimes be just fine.

Another common symptom of depression that can actually manifest from a tough situation (such as having the flu) is a loss of appetite, Muskin says. If your appetite gets back to normal after a few days, then you are likely not depressed.

"A change in sleep habits should always be of concern, but is not 'diagnostic' of depression," Muskin tells Romper. "Inability to fall asleep may be caused by anxiety, real life concerns about some issue in the person’s life, physical pain, or the start of a depressive or manic episode. Some people run over the day’s events before going to sleep and may ruminate about something that did not go well, or something they wish they did not say. This can be normal but it can be indicative of a psychiatric disorder."

Saying "I'm so depression" probably actually means you're not, since those with clinical depression aren't usually so open about it, Muskin says. What you probably mean when you say that you're depressed is that you are having a particularly difficult week and are feeling very sad or frustrated, and that's okay. Your feelings are still valid and deserve to be dealt with (whether with a bubble bath or with a professional), but are likely not a sign of clinical depression and will be temporary.