Deffective skateboard?

I have gotten 2 real crappy, cheap, Wal-Mart skateboards as I have just started skateboard. The k-tails & trucks always break or wear done quick. I am stepping up 2 a Zero with Independent trucks and much more. I haven't gotten it yet but the board I have now is warped. it's like if U took a popsicle stick between both of your index fingers and thumbs then twisted in 2 different directions. all the wheels never touch the ground at the same time. I think this may be affecting my progress in learning to ollie. Am I full of crap or do I really needthat new sk8board?