Little Injury, Huge Strength Down

I recently had a very minor ‘whole arm injury’, it seems that i got a nerve badly during some presses, and everything hurt from my left trap, up to my left hand . I rested for 5 days, and massaged it, and i did nothing for those 5 days (no squats, nothing with my right arm, and so on). It recovered completely. At least the pain did.

But all of a sudden my left arm got A LOT weaker after that. Both my pulls and presses, everything except my grip got tremendously weaker after that. That was a month ago, and its progressing VERY SLOWLY back to normal, albeit with no pain. My question is: Are BIG (permanent) DROPS common in minor injuries?

I’m saying ‘permanent’ because it doesnt feel like i am recovering my strength now, it feels more like i am building it up from scratch again in my previously injured arm.
Also, i had no previous injuries of any kind, and I am a healthy 23yr old male.

common? No. Possible? Yes.

Think of it as a minor injury that highlighted a major problem.

I’ll bet your shoulders are all jacked up. Fix that.