Do you have a trainer? If so, seek the opinion of another trainer. I agree with others in guessing that your footwork and tactical ability need some work. A good trainer will teach you to turn this to your advantage. A good tactical fighter will move in such fashion to allow the aggressive fighter to expend his energy and strength and gain very little. You, on the other hand, should be taught to closely watch a fighter like that and pick the right moment to throw your punches and where to place them. I recall sitting ringside during the Lewis-Tyson fight and watching Iron Mike come charging out like a bull during the first couple of rounds. Lewis seemed to hold back and you could immediately see he was a tactical fighter the way he moved around and let Tyson expend his energy.