Hey Carol. Nah. It's definitely not uncommon. The only thing that varies is the frequency of the bad emotions. Different for every individual. Yep. 16-19 was a more challenging stage for me. Yeah. I think it will always come and go. All the way through life. I happen to be going through another low state right now.
But I already know the contributing factors to feeling like this. eg. for starters I don't really have a social outlet right now.
Yeah. Even when you think you're doing everything you can to help yourself. It's still easy to lose hope sometimes.
Yes, there can be a deeper meaning to feeling stuck in a rut. It depends on your situation. It's important to trace all the possible reasons given your circumstances and your biology. You can experience the 'snowball effect'.
Take loneliness for example, a natural and primitive human emotion that helps us reconnect with our tribe, strengthening chance of survival. Carrying the burden of even isolation alone, can be enough to discourage us from feeling like committing to anything.
Knowing this kind of particular info is certainly helpful.
When you've found the reasons and you're doing them all but STILL feel bad, then it may be time accept that the day is an off day, or an off week etc. It's hard to come to terms with having to feel down. I believe this is the core source of the problem. We need to create RESONANCE within ourselves not RESISTANCE. Despite however bad we might want it to disappear.
Good work for reaching out. :)