The reason why Ash is pissed off is because he just can't kick the crap out Pokemon Hunter J like he can Team Rocket. In every battle he had of Team Rocket, from the lowest intern, to the highest Giovanni, Ash has always been victorious. Not with Pokemon Hunter J, she's cool, she's sophisticated, she's more concerned doing her job than fighting a bunch of brats whose balls haven't dropped yet. Ash can't win against her, Ash can't win against Paul, and Ash can't win against the feelings he has for people who piss him off.
Ash is a Tsundere.
Image attached is Ash's current English VA.