Sometimes horses display this irritated attitude when you are using too much and too sudden. NOrmally, I am all for using as much pressure as necessary. But, sometimes the horse needs you to ask with less the first time and give him a small chance to comply. If you go straight to whacking with the whip, it can provoke a defensive attitude. It' s bit like the horse that is alreeady trotting and the lunger keeps cracking the whip behind them . The whip just tell them to go if your body language doesn't do the trick.
Did you forget to "ask" before you "told?" Have you gotten big enough with him so that he knows how big you can get and will not want to go there, thus will respond to the first "asks" before you ever have to even get half way big?
Never forget to ask small, but also don't stay in the middle ground ,either. If he is resisting forward and you find yourself nagging, then you get bigger, fast! But go right back to small the ver next time you ask.
If he has a bit of an attitude such as ears back, well, as long as he is honestly going forward when you say, then he can have his opinioin,. IMO even a little bucking is of no real consequence. As he leader, you keep your eye on the goal , "Foreward at canter!" and disregard his tantrum.