Did I waste my noob gains?
You may have missed some easier early progress, but you did not ruin your future. "Noob gains" refers to the rapid early improvements many beginners get when they first start resistance training: better technique, improved coordination, rising strength, and primarily visible muscle growth. The body is responding to a new stimulus, and the learning curve is steep.
To "waste" noob gains would mean spending that beginner window with poor training, very low protein, insufficient food, bad sleep, no progression, inconsistent attendance, or random workouts that never create a clear stimulus-recovery-adaptation cycle. In that sense, yes, someone can fail to take full advantage of their easiest progress phase. But that is not the same as permanently losing the ability to build muscle.
Early progress is faster because there is more low-hanging fruit. Later progress is slower because you are more adapted, not because your opportunity is gone. You can still build strength and muscle by training with specificity, using progressive overload, eating enough protein, managing fatigue, and recovering well.
Regret is usually less useful than structure. Start from your current baseline, choose a simple plan, track your lifts, use good technique, recover, and progress gradually. The training you do consistently from here matters more than the perfect first year you wish you had.