Hey man, sometimes you just dont feel right. If it happens next time you pitch, then there might be a problem, but it was probably just one of those nights.
Same thing happened to me from time to time throughout my career. Usually the result of lifting too close to when I was pitching and not allowing enough recovery time.
Keep your head up. It’s one appearance of many, many more to come. The real question is were you able to use your other pitches effectively and still get the win? That’s the mark of a special pitcher.
For what it’s worth IMO the velocity loss is nothing to worry about unless it’s accompanied by some kind of pain in your throwing arm. I call it temporary dead arm.
Every year when preparing for the season, early on, my son goes through a period of feeling like he has no pop on his pitches. It seems to be just the arms natural reaction to “opening up” again and increased workload.
During the season you’ll go through it also. Heck even Sandy Koufax had trouble getting loose now and then.
I think it has to do with longer levers (i.e. bones) requiring more strength to accelerate. In growth spurts, the bones grow faster than the accompanying strength increases. So, until strength catches back up, velocity drops. Seems to make sense.
House told us that in some country (don’t remember which one), young athletes who grow “x” amount in “y” amount of time are removed from competetion for some period of time to allow them to play catch-up. I suppose one could be at an increased chance for injury in such a state. It’s an interesting concept.