I think you meant that he was kicking out at the bag on the whip, not you, correct?
You need to make the horse THINK about moving out onto the circle, then go forward. IF you keep applying pressure to his hind end, he will turn and look at this item, thus keep turning his face to you and his thought will not be about moving out and forward.
put the pressure on his face, to make him move away from it. this will move his head and face outward. And, put some pullon the leadline out in the direction you are going to want him to travel. Do these things and watch his ear and eye. When his ear and eye go out that way, then he is thinking about moving that direction. you have his mind going out that way, instead of in AT the rustling whip/bag or whatever you use to put drive on him.
Once he is looking out that way, a wee bit more pressure and a "cluck" will likely have him move out onto the circle. Once he does this, you can move and apply the pressure to move forward at his midline, roughly wehre your leg would put pressure on. Not too far back or he will move his butt away from it and turn to face this "thing. focus on his girth area to drive him on. Once he goes forward better, you can move the drive back a bit , but if he moves his butt outward, you make him take his front end away by focussing on his inside nostril and pushing that out and away from you.