Dude, from your pics, you are pretty small. I think some of you need to realize that your body has to adjust somewhat to training regularly. If you are a beginner, you can't expect to hop into this with full force and not feel any minor aches and pains. It is a signal to back off a little. However, bodybuilding is about finding your initial limits and pushing them further a little each time. Unless this pain is excruciating, some of this you just allow yourself to heal and attack the exercise again until your body gets used to it.
That is, assuming your form isn't complete crap and you aren't headed towards an injury. No one can see you perform the exercise over the internet. That means some of this will require your own footwork with regards to either watching others or having someone more experienced show you how to do it right. Someone more experienced does NOT onclude the guy who has only been lifting 6 months longer than you.