YngHungSFSD saidYou know for me and many guys I've trained with the key indicator of success is if I have progressed my workout from the last time.
This is the key bro, record your workouts, and try to improve some each and every time you go, and I guarantee you, DOMS or no DOMS you will grow as long as you eat right and rest.
You are lucky to be young in this regard. Of course when you get older you cannot progress as fast, are more prone to injury, etc. So when I push myself I have to be careful as even lately I was pushing my bench-press and had shoulder pain it took me a good month to get over. Joint pain, back pain, these are the things I have to watch out for and maybe even fall back in weight/reps. I did find though in the last few years, my body is responding to really eating more (protein mainly) and ok, some supplements.
I was a skinny 117 lbs at 20 years old when I started but have pushed as high as 180. But in my 30's, at some point I had to ditch the notebook because my progress was so slow it just discouraged me. That is when I switched to a "how I feel" approach. Had I not been such a slow gainer when I was younger, I probably would have stuck with a notebook. At the gym I go to, which can be very difficult to navigate at peak times, you are forced to improvise which can also hinder a strict plan.