Topic: need help with my gamecube controller?

hello! Can't seem to find help anywhere else, but I'm playing twilight princess for gamecube and I'm stuck due to the z button on my gc controller not working properly. I just got the master sword and I need to get out of the sacred grove and the only way out is to warp. Whenever I tap z to talk to midna, it automatically chooses the first option within the very split second the menu opens, so all I can really do is switch between human and wolf form since that's the first option. I've also tried opening the portal menu through the map, but when I press z to choose a specific portal to travel through, it just closes my map and then makes link dash and that's about it. It has been doing this since I first started playing the game, but only now is it becoming a real issue since, like I said, I'm trapped until I can either get it to work or buy a new controller for, which I really don't have the funds for at the time. Has anyone else had this problem before? Is there anything anyone can think of that could be causing it to act up? More importantly, how can i fix this? I really want to finish this game soon. Thanks!

Seems to me you need a new controller.