No you should not. Twitter has no native support for Tweets with Comments, and the usual way to do a RT with comment is by tweeting like the following:
Cool Tweet! RT @username Hey this is the original Tweet!
Usually a link is not included. (That is no convention enforced by Twitter, just something that got common over time)
This will not increment the retweet counter for the target Tweet, you should pass the original Tweet ID to the in_reply_to_status_id parameter.