You know, I was doing research last night and found some pics that looked exactly like those spines coming out of your skin. It was caused by a fish parasite called a camellanus worm. Worm is tiny and red, but the only visible sign of infestation are the spines protruding out of body. For fish, levamisole is recommended, but basically unavailable. Prazinquatel was also mentioned as being effective, which could be why you reported relief when using it.