No pain? Hmmm. I'll give you my thoughts, but there much more knowledgable guys on here. My first question is how far are you going on the negative stop point. You should not pass the point where your upper arms are parallel to the floor. If that is not the case, maybe you should bring your elbows in slightly to take some pressure off your shoulders ( this also transfers weight from the pecs to the triceps) good luck & don't cling your weights at the top of your rep.