as most people said DOMS common and some say ideal.
Overtraining, however, is not ideal. Everyone's body gives off different signals when overtrained...when i've overtrained my body usually feels hungover and weak and my joints generally ache.
from what your first post said though i'd put money on you just having a case of DOMS
M.Ed. Ex Phys
I see what your saying, But its weird for me. Like my biceps never get sore anymore. My chest gets sore when i switch exercises routines, like when i go from low reps heavy weight to high reps with lighter weight. But yeah i think ive fianlly found out how my body feels when im overtrained. Its a crappy feeling. I feel lethargic, had little motivation to train, weak, i kinda wanted to train, but i knew i should NOT be training.