I got a similar injury recently while doing the "clock choke" (I was 1/2 on his back reaching around his neck to grap the lapels). He was underneath me, on my left side. As I was straightening my arms and bringing my legs forward to sit out to apply the choke, I had a strong deep pain in the left center of my sternum/ribcage. More of a severe throbbing, not sharp. Now, 2 days later, it only hurts if I do like an ab crunch or clench my muscles in that area or if I push with hard pressure right over that spot under my left pec.
It's a concern to me. I guess i can't train for a bit.
