Remorse need not have to do with conscience. That is to say one can feel guilty or regretful after the fact even without a well-developed conscience, particularly if someone draws our attention to the fact that we have behaved regrettably or badly. Conscience is a moral compass - the ability to discern between good and bad, even before  an action or while we are engaged in an action. Those who listen to their conscience can avoid a bad thing happening through conscious decision. Those who allowed a bad thing to happen out of not thinking (not feeling) or out of simply being mean, stupid or cruel, may or may not feel remorse afterwards. There are people without conscience and without the capability of desire to feel remorse, and there are people with conscience and the capacity for remorse, and there are people without developed conscience but the ability to feel remorse. The point is that remorse is what you feel after the bad thing has been done and that there are forms of bad things that are so bad that no amount of remorse will undo the damage. Consequently, the voice of conscience can help us avoid things that might afterwards cause remorse. Conscience can be preventive, while in some "after the fact" situations, no amount of remorse can undo the damage that has been done. Pangs of conscience, specifically, can be similar to remorse in the sense that ordinarily pangs of conscience can also bother one after a bad or unfortunate deed. Pangs of conscience are the first hints that one has screwed up, whicle remorse is longer-term regret that may also go deeper. 

 Remorse is sorrow over something you have done wrong.

 Pangs of conscience are times when you think "Oh dear!  I should not have done that"  They may have a different source than remorse.  Pangs of conscience may result from fear that you will get caught, or  you may be remembering someone who taught you right from wrong.