I’m not depressed but I’m not normal

im not depressed but im not normal either. I’ve been depressed before and I’ve been normal before too. I’m neither right now I’m in the middle. I just feel down everyday and it’s been going on for years. Like yea I can mask it for an hour when I go out and have fun hanging out with someone but deep down inside something must be bothering me that I can’t pinpoint or some kind of level in my body must be off. Has anyone else experienced this before and what is it?