Such pain usually indicates weak links are being strengthened. There is in all likelihood nothing to worry about. A cramp most likely haha. Especially between scapula, since they brace for bench it's quite common to get pain there. Just work it out with some dynamic and active resistance stretching. Do pulls like DB row and get a good stretch and row it out. The pain will disappear on bench. 60% of max is good for the rows but do whatever. Sets to failure. 3x a week at least.