Acute Hand-Arm (Nerve) pain (?) after Acupuncture session

[CCVJ]

About 2 weeks ago I had an acupuncture session, en left with a pain that is still there. I have acupuncture quite often, and although it's usually a bit painful (I'm very sensitive to needles) it usually does help. Last time I went to the therapist for treating injuries in my feet, he put a needle in my wrist, between the thumb and the lower arm (between scaphoid and radius). The pinch hurt more than usual, and irradiated at the very first moment through the thumb, but I managed to handle the pain. The needle kept moving for about 45 minutes (as it was right on top of the place where one takes the heart-beat), but the therapist saw no problem with it.

After the session, I'm not able to stretch my arm completely (specially when the thumb creates a slight extension), and the pain seems to follow up to the antecubital space. The thumb feels colder than the other fingers and a bit numb at the tip. Since I'm a musician (pianist), I'm very concerned, because it makes it very painful (if possible) to play with my left hand.

Should I be worried that this could get worse?
Does anyone know if this is some kind of peripheral nerve injury, and or id there are good treatments for it?