Do you ever get into working out, but reach a point when you feel like nothing’s working? (Please read details)

I’ve been working out regularly for maybe a month or so now. Not trying to lose weight, I just want to build muscle and get a bit more toned.
Lately, I finish working out feeling like I didn’t really do anything. I don’t get the soreness in the morning like i would weeks ago. It leaves me feeling very unmotivated. Does anyone have any tips on how to overcome this?
Sorry if this post doesn’t make a whole lot of sense, I don’t really know much about fitness.