I seriously doubt this has to do with the strength of your Master. It simply seems he is not overly concerned about your extroverted behavior. In your post you say, "I feel like I take over and I don't want that." You never mentioned if your Master seems displeased so I am left to assume he is not bothered by your actions. Many Masters have policy and protocol regarding such things, but if it hasn't been discussed it just might not be one of his hot buttons. So if you're not offending him, per se, punishment seems out of order. Instead, explain to him that you would like his help in an area you feel you need to grow in as a submissive. Share with him what you've shared in the post and the two of you should be able to work out a way to curb behavior that seems to take you out of your submissive frame of mind. There were a few great suggestions above as to how to do so, so I won't be redundant by throwing out similar advice in that department.

Best of luck, let us know how it goes!