When it's no longer practice pain

Here's the clear line. Pressure pain at the fingertips and mild muscle fatigue are normal early companions. Persistent, sharp, or stabbing pain in joints, wrist, or tendons — or numbness, tingling, or loss of strength in fingers and hand — are not. Such signs don't mean "keep going," but: stop and have the cause checked by a doctor. That's no remote diagnosis and no reason to panic, simply the responsible line — the body is reporting something other than practice pain here, and that belongs in expert hands, not in the next practice session.