The midfielder was forced off the pitch shortly before half-time following a clash of heads with with Villa striker Juan Pablo Angel that left him nursing a big lump on his forehead.
JJ revealed he had to take it easy over the weekend and has avoided exercises such as diving headers since returning to training.
"I went up for a header and that is probably the last I remembered of it until I got back to the changing room," recalled the 22-year-old.
"I sat in a room with the lights down a bit and gradually I felt alright. The doctor was with me, checked my eyes and I had a bit of a headache.
"I just stayed in after that, my girlfriend came round and looked after me, I watched Match of the Day and that was it.
"They've were cautious with me in training and I've just done the physical side, rather than the match play."
JJ's afternoon being cut short was a blow for both the player and team due to the fact that his speed was beginning to become a telling factor down the right flank and he generally seemed to be getting the better of his marker.
"It was very unlucky, I had got into a few good positions down that right hand side. Gareth Barry is a good player, but I felt I had the beating of him on the day so it was a shame it had to end like that.
"Luckily enough for us, we've got the likes of Aaron Lennon to come on."
Jermaine Jenas reports he has suffered no lasting ill-effects from the heavy bang on the head he suffered against Aston Villa on Saturday.