Not Myself

I have noticed I haven't been feeling myself lately. Im not going to say I'm depressed to the point where I should talk to someone, but I just don't feel like myself. Just really down on myself. I'm not sure what I can do to pull me out of this funk. I've stopped working out. I'm tired all the time(no I'm not pregnant). I just don't feel motivated to do anything. I feel so stressed out. I just hate feeling like this.