Most instructors recommend shoes with thin soles so that you can easily feel the pedals. One of my low hours students switched from trainers to shoes with a thin sole, and he told me it made a tremendous difference. It's true that eventually you can fly wearing just about any type of footwear, but you only have 12 hours and you're struggling, so I'd suggest giving this a try and seeing if it works.
One thing that worries me about your post is that you say your instructors laugh if you ask about footwear. They shouldn't; it's a serious question, and it's wellknown in the instructing world that in the beginning footwear can make a great deal of difference. But in any case, they should take ANYTHING you ask seriously!!!! If this is their general attitude to you, maybe you should consider changing instructor/school. As for them thinking you're trying to kill you, of course they do, because you probably are!
But don't worry or take it to heart; we all know it's not intentional - it's just what students do.
