It’s natural to have a mixture of good and bad days-and average ones, too.

But if you’ve felt a bit more down than usual, it could be due to depression. Feeling sad and experiencing a loss of interest in stuff you used to enjoy are the two main things to look out for as you assess your mood. Here’s a list of additional depression symptoms you should be aware of:

• Irritability
• Overreacting
• Changes in appetite
• Sleeping a lot more—or less
• Moving slowly
• Restlessness
• Forgetfulness
• Trouble focusing
• Feeling tired or low energy
• Feeling worthless or guilty
• Even thoughts of death or suicide

If you have two or more of these symptoms for over two weeks, you may have depression. (Or you might be headed in that direction.) And, if those symptoms are causing problems at home, work, or school, you should see a doctor, counselor, or therapist to discuss what’s going on. Depression doesn’t usually go away on its own, so finding out if you have it is the first step to getting past it. It’s important to remember that you can overcome depression symptoms with help.

Fortunately, you have quite a bit of control over your mood, even on challenging days. Positive thoughts, activities, and feelings can actually be used like tools that lift you up when you’re down.

That’s why mood tracking is so cool. When you track your mood and map it to thoughts, activities, and feelings, you can see patterns that work for you and against you. Keep doing what you do on the good days and you’ll affect your mood for the better.